Learning scales from one root-the Satriani way

[curiousgeorge]

After reading multiple magazine lessons with Satch including the Guitar Secrets book, it seems as though he prefers to teach his students to play scales off of one root note when learning how to visualize scales on the fretboard (the parallel rather than derivative/relative way). I find his method of playing scales over a droning bass note is a great way (and fun!) to internalize the differences in intervals and scales, and which ones go together nicely and which ones don't. I'm wondering if he is opposed to teaching the relative way, or what his reasons are for tirelessly promoting parallel or pitch axis scale practice. I'm assuming that its because you have more options when playing over a progression, but I would like to see what everyone's opinions are of this method, as well as some explanations as to the pros and cons of each method, and which is best. I would think that it is best to learn both in order to have a clear vision of scales on the fretboard. Again, another assumption. Please enlighten us... :)

[Malcolm]

I'm assuming that its because you have more options when playing over a progression, but I would like to see what everyone's opinions are of this method, as well as some explanations as to the pros and cons of each method, and which is best. I would think that it is best to learn both in order to have a clear vision of scales on the fretboard. Again, another assumption. Please enlighten us...
IMHO ------ Once I went to parallel modes I never looked back. With relative modes you have the same notes, with parallel - as you mentioned - you have extra notes to draw your solo from. Your pallet has more on it.

Again IMHO ----- Modes are a passage thing, something we have to work through ------ so yes learn both ways, and then pick the one that works best for this specific song. Just another tool in your tool box.

Malcolm

EDIT} Just thought of why I really like parallel. The specific mode charastic note, i.e. Dorian's natural 6, Lydian's #4 etc. I look upon those the same way I look upon the blue note in the blues scale --- to be added when you need it

[JonR]

After reading multiple magazine lessons with Satch including the Guitar Secrets book, it seems as though he prefers to teach his students to play scales off of one root note when learning how to visualize scales on the fretboard (the parallel rather than derivative/relative way). I find his method of playing scales over a droning bass note is a great way (and fun!) to internalize the differences in intervals and scales, and which ones go together nicely and which ones don't. I'm wondering if he is opposed to teaching the relative way, or what his reasons are for tirelessly promoting parallel or pitch axis scale practice. I'm assuming that its because you have more options when playing over a progressionNot really. This is one of the main areas of confusion regarding modes. In any normal progression (a chord sequence in a key) there is only one correct mode for each chord - and it's the same scale for all the chords (scale of the key). If you apply a different mode, you incorporate wrong notes, and the sequence becomes disjointed.
(There is a slight area of leeway on tonic chords. Eg, you can sometimes impose lydian or mixolydian on a major tonic, instead of standard Ionian. And you can sometimes impose dorian or melodic minor on a minor tonic, instead of aeolian. But that's about it.)

Satriani's method is great for understanding the sound differences between modes, of course, which is important in composition. So if you want a particular mood for a tune of your own, you have those choices. But you can't impose a mood that way on an existing tune; its modal sounds are already there - and you don't have to know or care what they are, you just use the scale of the key (paying attention to chord tones).

But the relative method is also flawed, in that the mode names are pointless. They are just names for different positions of the same scale. The important thing is to learn that one scale in all ("modal") positions, but forget mode names, because they have no impact when improvising. A "B phrygian" pattern on an Em chord is an E aeolian sound - just as an "A dorian" or "G ionian" one is. So the mode names are misleading.

Better to go with Satriani's method if you want to learn about what modes really are - how the sound depends on the tonal centre, not the fret pattern. But don't get the impression it's much use for playing in key-based chord progressions. (I would bet he doesn't promote it in that way.)
Even in modal music, the composition - not the improviser - sets the modes.

[jimc8p]

I like to see relative modes as a neat coincidence. It's coincidental that F Lydian shares the same notes as E Phrygian, for example. You might ask how such a striking relationship could be irrelevant, but if anyone has played with relative modes it should be obvious why. The relationship that exists is precicely WHY relative modes are irrelevant to each other - they are all THE SAME! -In any given context there will be absolutely no distinction between them.

For that reason, the only proper way to think about modes is in relation to themselves, as single scales. All 84 of them. Group them by the 12 different roots and you have the much more useful sets of parallel modes. This is the only way you're gonna hear their effects, whether you realise or not! The flavor of modes is created by the *parallel* diatonic comparison.

Satriani pitch axis, like the name says, involves selecting from the array of scales from the same root to play over a drone. (Parallel modes and scales.) It's a cool idea, but not really that musical to me. Like moving from Lydian to Phrygian Dominant is not really very intuitive. I think there are more sophisticated ways of modulating like that.

On the topic of pitch axis and parallel modes though, one thing you can do to create a backing track is to use common (neutral) tones. Try retuning the A string to B, and the D and G strings to E. That will create an open E5 chord (R, 5, R, R, 5, R.) Barring at the 7th fret gives you a B5 chord. So you have two quite full-sounding tonic and dominant chords using just three notes - E, F#, B (R, 2, 5). You can also use an E5/F# type chord as a II. Have some good rhythmic stuff going on, use octaves, use 5th, 7th and 12th fret harmonics and you can build up quite a complex, harmonic-sounding backing track. The cool thing is that it will be neutral to E lydian, ionian, mixolydian, dorian and aeolian so you can modulate away to something a bit more exciting than a drone!

You can use modulation with more sophistication, but depends what you're doing. If you're creating melody over a fixed progression, you will generally be governed by those chords. But, over the tonic chord you can quite easily modulate to an adjacent scale. For example in Eleanor Rigby, The Beatles use a major 6th over the minor tonic to create a passing Dorian sound. You can also modulate to adjacent scales where the other chords fit. For example, iii, V and vi are common to the parallel Lydian. So if you have a section in a C major/A minor song that goes Cmaj7, Emin, G, you can safely modulate to C Lydian for a nice effect.

If you're creating the chords and melody, then things are obviously very open to modulation. You can create a full key modulation, usually to the two adjacent parallels or the minor/major parallel. For example, the beginnning of Moonlight Sonata modulates from minor to major. Modulation is also one of the only circumstances in which relative modes can be 'used'. It works because the scales are employed individually, but linked via their relation. Modulating from, say, A minor to C major is common. Modulating to other relative modes as 'key scales' is much harder. Eg. REM's Man on the Moon has C Lydian verses and G major choruses. Not key modulations in the traditional sense, but still a deceptive tonic movement. So, although the relationship between F Lydian and E Phrygian is irrelevant, you could potentially link their *individual* contexts.

[JazzMick]

I never really put emphasis on visualizing scales or practicing them in any particular way.

It has always been more a matter of being melodic with the notes in question. Or more importantly, the harmony/chord I am sitting on.

Once you begin developing melodic ideas (something you should do the moment you learn a scale), the concept of 'visualizing' a scale becomes a bit redundant. Since when you see it as a whole your just seeing the same series of notes flipped and twisted around.

If you have to visualize anything, see it as some kind of melodic movement. Either as a lick/phrase or maybe just an interesting series of intervals that are open for improvisation.

Once you learn half a dozen ideas on that scale, and learn them in all possible positions. You will not only have the scale at your immediate disposal, but half a dozen useful melodic ideas to begin improvising with.

[curiousgeorge]

But the relative method is also flawed, in that the mode names are pointless. They are just names for different positions of the same scale. The important thing is to learn that one scale in all ("modal") positions, but forget mode names, because they have no impact when improvising. A "B phrygian" pattern on an Em chord is an E aeolian sound - just as an "A dorian" or "G ionian" one is. So the mode names are misleading.


This is where I will have to respectfully disagree. Here is a quote from a Satriani lesson from 2002:

"Though thinking of the mode as being the same as some other major scale is a very useful learning device, it is only when one fully understands and internalizes the sound of each mode's intervallic structure that one will master the modal concept. One day, back when I was in my first year of music college, I was taking a piano lesson when my teacher and I came to a particular section of improvisation. I said, 'This is in the Dorian mode.' My teacher said, 'Well, it's really the same as playing in G major.', but I disagreed. I said that if I'm playing in A Dorian, I'll emphasize the notes differently than if I were thinking G major."

I tend to side more with this approach, and thus I don't think that mode names are irrelevant.

[JonR]

This is where I will have to respectfully disagree. Here is a quote from a Satriani lesson from 2002:

"Though thinking of the mode as being the same as some other major scale is a very useful learning device, it is only when one fully understands and internalizes the sound of each mode's intervallic structure that one will master the modal concept. One day, back when I was in my first year of music college, I was taking a piano lesson when my teacher and I came to a particular section of improvisation. I said, 'This is in the Dorian mode.' My teacher said, 'Well, it's really the same as playing in G major.', but I disagreed. I said that if I'm playing in A Dorian, I'll emphasize the notes differently than if I were thinking G major."
Right, that may be true. But the differences you (or he) achieve are not modal differences.
(I notice he doesn't say what that section of improvisation was - what the chords were - but his teacher may have been quite correct.)
It's good if a different pattern can encourage you to find different kinds of phrases or emphases over a particular chord. But the difference is nothing to do with modes. It's merely to do with stressing a different chord tone or extension, or set of extensions. The mode is the same.
If the chord is G, then there is no way an A dorian pattern will give you an A dorian sound. You may get an emphasis on the 9th of the chord (A) or the 11th (C), or whatever, which may (or may not) be cool. It isn't dorian.

So - IMO - it's better to understand the sounds you're getting as they actually are: as they are defined in traditional terms (chord tones, extensions, etc).

[jimc8p]

One day, back when I was in my first year of music college, I was taking a piano lesson when my teacher and I came to a particular section of improvisation. I said, 'This is in the Dorian mode.' My teacher said, 'Well, it's really the same as playing in G major.', but I disagreed. I said that if I'm playing in A Dorian, I'll emphasize the notes differently than if I were thinking G major.
I'd also bet on the piano teacher being right. Emphasising notes within the key will have absolutely no impact on modality or tonality. Relative modal passages are possible, but they are governed solely by underlying harmony.

[curiousgeorge]

[QUOTE=jimc8p]I'd also bet on the piano teacher being right. Emphasising notes within the key will have absolutely no impact on modality or tonality. Relative modal passages are possible, but they are governed solely by underlying harmony.[/QUOTE/]

OK, I don't quite get ya....Is that not a contradiction to say that "emphasizing notes within the key will have absolutely no impact on modality or tonality" and then "relative modal passages are possible."? The teacher was obviously playing a minor vamp, so leaning on certain intervals such as the major 6th and minor 2nd is necessary give the A Dorian tonality. Why would he be emphasizing the modal notes from G major? It surely would not sound like Dorian...Is it not better to think of A Dorian as a separate entity unto itself? I'm not trying to be difficult...I just want to get a firm grasp on this stuff so I know how to approach it properly... :)

PS- if any of you guys are interested in Satriani's approach to learning scales and theory and whatnot, here are a few lesson vids in which he explains his ways in detail. (if you couldn't tell, Satriani influences me as much as Hendrix influences him):

OLDER

Chords and Arps:

http://video.google.com/videoplay?docid=6200928944138102607

Scales and Soloing

http://video.google.com/videoplay?docid=1659142068355085865&q=&hl=en

MODERN

Modes 1:

http://www.youtube.com/watch?v=ZTQolymKmDA

Modes 2:

http://www.youtube.com/watch?v=DCdZwASSKuk

[jimc8p]

put simply, improvised melody can have no impact on the tonality of music.

If the chord is G, then there is no way an A dorian pattern will give you an A dorian sound. You may get an emphasis on the 9th of the chord (A) or the 11th (C), or whatever, which may (or may not) be cool. It isn't dorian.

[curiousgeorge]

put simply, improvised melody can have no impact on the tonality of music.

Ok, can you explain why then? For example, what if you have no 3rds in your chords?...then you can define a major or minor tonality with the melody by playing major or minor 3rds...

"If the chord is G, then there is no way an A dorian pattern will give you an A dorian sound. You may get an emphasis on the 9th of the chord (A) or the 11th (C), or whatever, which may (or may not) be cool. It isn't dorian."

That's obviously understood. We can assume that Joe's teacher was not playing a G chord if Joe was playing A Dorian.

[jimc8p]

I see what you mean - eg. if you have a progression that could fit two modes you could define the mode with the melody...but what you couldn't define is the tonal centre.

So although the chords in joe's lesson probably became 'ii-centric', the key was not necessarily Dorian (hence the teacher's comment.) Joe's reasoning (resolving to ii chord tones) does not indicate Dorian tonality - you're always resolving to chord tones and will "emphasize the notes differently" even in passing.

Anyway, the point of this really is that the vast majority of the time, thinking in relative is neither theoretically or practically useful. All you really need on both accounts is the single key scale.

[curiousgeorge]

OK, cool...I thought maybe there would be holes in seeing scales on the fretboard with the parallel approach. I'm guessing you could also apply that method to harmonic and melodic minor modes as well as exotic scales.

[JonR]

The teacher was obviously playing a minor vampHe was? How do you know? That isn't mentioned in the quote you gave.
At least, it's ambiguous:
I was taking a piano lesson when my teacher and I came to a particular section of improvisation. I said, 'This is in the Dorian mode.' My teacher said, 'Well, it's really the same as playing in G major.', but I disagreed. I said that if I'm playing in A Dorian, I'll emphasize the notes differently than if I were thinking G major."It sounds to me like Satriani had decided he was (going to play) in dorian mode.
Otherwise I don't understand why the teacher would have said what he did.
There is no mention of the musical context (key-based sequence? single chord? modal vamp? free improv?) - but if teacher was playing a minor vamp, then it would have made no sense to say it was "in G major".

Of course, we are getting this story several stages removed from the original conversation, let alone not knowing the precise musical context.
So we can't really judge Satriani's view from this quote.
But the facts remain about the relationship between modes and keys - if properly defined.
Satriani is not stupid, and I suspect he knows the differences very well (I'd be very surprised if he didn't).

Firstly, relative modes (same notes) make no modal difference whatsoever.
Secondly, you can't make parallel (same root, different notes) modal changes to a key-based, functional harmonic sequence, without disrupting the sequence (with the exception of the tonic chord, which is, in a sense, independent of the sequence).
You CAN, of course, make other changes to change the mood or expression: you can play it faster or slower; louder or softer; higher or lower; and with other changes in articulation, tone or timbre; etc etc.
And you can add chromatic notes for colour - as contrast with whatever the "home" key/mode is.

But a major key piece is an Ionian modal piece - throughout. By definition. A minor key piece is mostly Aeolian mode, with occasional harmonic or melodic minor alterations.
Other modes are different tonalities, outside of keys - and actially pretty common in rock and jazz; at least mixolydian and dorian are.

[electrik noize]

In the third video that was posted of Satch (modes #1 I believe), he makes a couple of references about a "modal chord" sequence. As in starting on C as a tonic and playing a sequence of chords based on C Dorian and then finding a similar sounding mode (maybe natural minor..?) and, again starting on C as a tonic, use that to change up the feeling of the song. So verse one is in a C Dorian kinda vibe while verse two is in a C Aeolian kinda vibe.

Seems like an interesting idea but how in the world to you go about actually doing that?

[curiousgeorge]

He was? How do you know? That isn't mentioned in the quote you gave.

Well, it could have been free improv or whatever, but it was in the context of an article written by Satriani introducing modal theory, so draw your own conclusions. I would assume he was trying to show newfound superior modal knowledge over the teacher....

At least, it's ambiguous:
It sounds to me like Satriani had decided he was (going to play) in dorian mode.
Otherwise I don't understand why the teacher would have said what he did.
There is no mention of the musical context (key-based sequence? single chord? modal vamp? free improv?) - but if teacher was playing a minor vamp, then it would have made no sense to say it was "in G major".

Even if the teacher was playing a minor vamp, then why couldn't he have said it's the same as playing in G major? He was likely referring to the fact that A Dorian belongs to the key of G major, and the pattern that covers the entire fretboard encompasses 7 modes, including A Dorian. At least, this is my interpretation, but of course I am probably missing something here... :rolleyes:


But a major key piece is an Ionian modal piece - throughout. By definition. A minor key piece is mostly Aeolian mode, with occasional harmonic or melodic minor alterations.


OK, but I don't understand why you can't use the Lydian mode, for instance, as the I chord in a major key piece then...

[jessmanca]

OK, but I don't understand why you can't use the Lydian mode, for instance, as the I chord in a major key piece then...

You can...

But, the raised 4th degree of Lydian tonicizes the 5th degree, which is the relative Ionian. Making your I chord sound like a IV chord. But you can certainly use modal mixture if that's what you're going for.

What they're talking about is playing over a Major progression... Anything but a major scale would sound a bit out to most ears.

[jimc8p]

So verse one is in a C Dorian kinda vibe while verse two is in a C Aeolian kinda vibe.

Seems like an interesting idea but how in the world to you go about actually doing that?
C Dorian chords:
Cm-Dm-Eb-F-Gm-Adim-Bb

C Minor chords:
Cm-Ddim-Eb-Fm-Gm(or G7)-Ab-Bb

Making chord sequences is pretty easy when you have the chord menu laid out. You just have to be mindful of C Dorian sounding like Bb Major. (Put a lot of focus on the chord you want to be the tonic.) You can also mix them together, eg. borrowing the classic Dorian chord for an Aeolian/H.Minor sequence (in this case F).

OK, but I don't understand why you can't use the Lydian mode, for instance, as the I chord in a major key piece then...
This would be parallel modes right? You can do that, especially when the context is open as I was describing before. If however the context is well-defined, eg. I-vi-IV-V, an augmented fourth is gonna sound terrible anywhere!

[JonR]

Even if the teacher was playing a minor vamp, then why couldn't he have said it's the same as playing in G major? He was likely referring to the fact that A Dorian belongs to the key of G major, and the pattern that covers the entire fretboard encompasses 7 modes, including A Dorian. At least, this is my interpretation, but of course I am probably missing something here... :rolleyes: Well, as I said, we simply don't know the whole context. You might be right.
My suspicion was that it was a sequence in the G major key (that would fit the quotes). But I don't know.

OK, but I don't understand why you can't use the Lydian mode, for instance, as the I chord in a major key piece then...You can, of course. The tonic chord is - as I said - an exception.
The jazz convention of using a lydian tonic in a major key (ionian) sequence is based on the notion that lydian is a stable tonality. Every note of lydian mode can be used as a chord extension, so a soloist is totally free to stress any note he/she wants.
With an Ionian tonic, they need to avoid the 4th - or resolve it quickly to the 3rd.

[JonR]

C Dorian chords:
Cm-Dm-Eb-F-Gm-Adim-Bb

C Minor chords:
Cm-Ddim-Eb-Fm-Gm(or G7)-Ab-Bb

Making chord sequences is pretty easy when you have the chord menu laid out. You just have to be mindful of C Dorian sounding like Bb Major. (Put a lot of focus on the chord you want to be the tonic.) Exactly. And probably best to avoid the Bb chord altogether, or at least not precede it with F7.
Most dorian sequences only involve 2 chords. I-IV, or i-ii.
If however the context is well-defined, eg. I-vi-IV-V, an augmented fourth is gonna sound terrible anywhere!Not necessarily. In a ballad, especially, a #11 on a tonic maj7 sounds good.
Of course, you wouldn't use that #11 on any other chord.
Eg, in a sequence in key of C, the only place for an F# note is on a Cmaj7. (Not counting a D7 secondary dominant, that is... ;) )

Having said that, Jimi Hendrix used a C# note on a Bm chord in key of G (Little Wing). That's because major 9ths sound good. (He probably wouldn't have used it as a #11 on his tonic G, tho.)
IOW, there are all kinds of subtle stylistic sub-rules and conventions here, which require a tasteful ear to navigate.

[jimc8p]

Exactly. And probably best to avoid the Bb chord altogether, or at least not precede it with F7.
Most dorian sequences only involve 2 chords. I-IV, or i-ii.
Actually the VII chord is one of the most useful. It resolves naturally to the Dorian tonic in the same way it does in Aeolian (deceptive cadence). The other chords can be used too. Here they all are, mostly used in passing to enhance the interest of static harmony, though a little function in there:
Cm-Cm-Gm-F
Cm-Cm-Eb-Dm
Cm-Cm-Bb-Adim
Cm-Cm-Eb-Bb

In a ballad, especially, a #11 on a tonic maj7 sounds good.
Of course, you wouldn't use that #11 on any other chord.
Eg, in a sequence in key of C, the only place for an F# note is on a Cmaj7. (Not counting a D7 secondary dominant, that is... ;) )

Having said that, Jimi Hendrix used a C# note on a Bm chord in key of G (Little Wing). That's because major 9ths sound good. (He probably wouldn't have used it as a #11 on his tonic G, tho.)
IOW, there are all kinds of subtle stylistic sub-rules and conventions here, which require a tasteful ear to navigate.
Obviously the #4 is the notorious blue note in major and minor. Generally speaking though this is only passing tone material in a key, IOW has no Lydian relevance right?

Although, talking of secondary dominants, music often leans keys either way around the circle of fifths. eg. leaning C major to either F major or G major (or thinking of it another way leaning C Ionian to C Mixo or C Lydian). That's why you'll often have ambiguous sections and scale modulations that open up the modality as well as the tonality. For instance, the use of the I7, bVII, v etc.

[Theodds]

Satriani is a pioneer of the very method of viewing modes that JonR is calling incorrect. He might move the Lydian mode straight up over a number of different roots (e.g. playing Amaj9#11, Bmaj9#11, Cmaj9#11 Dmaj9#11 as the chords of a song - John Mayer does something similar to this right before the solo in Neon for reference), soloing in Lydian over each. Or, he might take a static root of - let's say D - and change the modes he uses over it. You might end up with a progression of Dmaj9, Dmin9 D7, Dmin(maj7), and make a logical scale choice over each. These aren't just learning tools; they are things he actually does in his compositions. And, personally, I think they sound great. Lots of artists are labeled "progressive" because they fit some preconceived notion of what it means to be progressive, but Satriani is a composer who is actually moving popular/rock music in a totally new direction.

[JonR]

Actually the VII chord is one of the most useful. It resolves naturally to the Dorian tonic in the same way it does in Aeolian (deceptive cadence). The other chords can be used too. Here they all are, mostly used in passing to enhance the interest of static harmony, though a little function in there:
Cm-Cm-Gm-F
Cm-Cm-Eb-Dm
Cm-Cm-Bb-Adim
Cm-Cm-Eb-BbAgreed - those all work.
Obviously the #4 is the notorious blue note in major and minor. Generally speaking though this is only passing tone material in a key, IOW has no Lydian relevance right? Right. Blues is a quite different tonality. The b5/#4 of blues is not a chord tone. It's an expressive melodic pitch, of variable frequency, usually resolving to 4 or 5 before going on elsewhere.
The lydian #4 is a #11 chord extension, harmonising with maj7 chord intervals below: 1-3-5-7-9. (Has to be a major 3.) It doesn't need to resolve anywhere.
In true (medieval) lydian mode, AFAIK, it would resolve up to 5, or get flattened in order to resolve down to 3. But that's not what "jazz lydian" is about: it's a complex harmonic (consonant) sonority, rather than a melodic (modal) tonality.

In this, it's similar to the way jazz uses tonic melodic minor. Classically, melodic minor is - duh! - a melodic device, employed to strengthen resolution to an upper tonic (which is why it's ascending only). In jazz, melodic minor is a harmonic device, employed because the maj6 and maj7 sound nicer as chord extensions on a minor chord than b6 and b7 do. (Actually b7 sounds fine, but it gives the wrong harmonic signals.)
Although, talking of secondary dominants, music often leans keys either way around the circle of fifths. eg. leaning C major to either F major or G major (or thinking of it another way leaning C Ionian to C Mixo or C Lydian). That's why you'll often have ambiguous sections and scale modulations that open up the modality as well as the tonality. For instance, the use of the I7, bVII, v etc.Yes, this is very true of rock. Classically - and in jazz - cycle progressions move anti-clockwise round the circle of 5ths: B-E-A-D-G-C, etc. In rock, they (we!) like to go the other way, using plagal cadences: C-G-D-A-E. Rock thinks anti-clockwise is cheesy! (The secondary dominant, V/V, is a typical indicator of country music; so any time a rock band wants to inject a little "yee-ha", you'll likely hear a V/V, eg, an A chord in key of G moving to D. Eg "Honky Tonk Women".)
Rock also prefers mixolydian to ionian, so will usually include a bVII chord in a major key. If they use the maj7 of the key, it will probably be in a descending bass line (eg G-D/F#-Em), not in an upward resolution to the tonic.

[jimc8p]

Satriani is a pioneer of the very method of viewing modes that JonR is calling incorrect. ... These aren't just learning tools; they are things he actually does in his compositions. And, personally, I think they sound great. Lots of artists are labeled "progressive" because they fit some preconceived notion of what it means to be progressive, but Satriani is a composer who is actually moving popular/rock music in a totally new direction.
I don't think anyone said anything was incorrect. It's just important to realise that pitch axis is a tool for composition, not improv. It's also important to realise that relative modes (not connected in any way to pitch axis) play absolutely no role in improv.

Satriani is popular for a reason, he has soul and originality. Although pitch axis in itself, imo, is a bit of a gimmick.

[JonR]

Satriani is a pioneer of the very method of viewing modes that JonR is calling incorrect. He might move the Lydian mode straight up over a number of different roots (e.g. playing Amaj9#11, Bmaj9#11, Cmaj9#11 Dmaj9#11 as the chords of a song - John Mayer does something similar to this right before the solo in Neon for reference), soloing in Lydian over each. Or, he might take a static root of - let's say D - and change the modes he uses over it. You might end up with a progression of Dmaj9, Dmin9 D7, Dmin(maj7), and make a logical scale choice over each. These aren't just learning tools; they are things he actually does in his compositions. And, personally, I think they sound great. Lots of artists are labeled "progressive" because they fit some preconceived notion of what it means to be progressive, but Satriani is a composer who is actually moving popular/rock music in a totally new direction.Agreed.
The dispute is about whether modes have a useful role when improvising over a key-based composition. Basically, they don't. Improvising over a given tune is about identifying which scales (or modes) are used in the composition, and then using the same ones.
Eg, given that chord sequence - Amaj9#11, Bmaj9#11, Cmaj9#11 Dmaj9#11 - you wouldn't "apply" mixolydian modes on each chord, right? You'd get 2 wrong notes per chord.
Likewise, there's no point thinking "F# dorian" when soloing over Amaj9#11 - it's exactly the same notes as A lydian, and the dorian notion has no effect (other than in your mind).
The correct strategy is to identify maj9#11 chords as lydian and play the appropriate scales - knowing that "A lydian" runs all the neck, as patterns of E major (or whatever else you want to call the patterns).

What was not clear from the original quote of Satriani's was what the context was of the disagreement between him and his teacher, about the difference between "A dorian" and "G major". In some situations there's a clear difference. In others, no practical difference at all.