Re: What theory taught me...
Is this the way to think about the key-mode relationship:
This is the way I've come the think of it right or wrong....
The bottom line is that nobody uses modes "literally" but noob shredders and noob rockers. Experienced players (rockers and shredders included) may or may not think in terms of modes, but if they do use them, they do so in a fashion that makes it extremely difficult to identify that as their method. They mix up the melodic intervals such that even if it is modally derived, the listener can't tell.
Furthermore, if you analyse what they play then you may find the use of this mode or that, but that is strictly open to interpretation. Another analyst might come along and identify a completely different set of modes that come into play from the same passage. In the mean time the person may not have even been thinking about modes at all when they played it. Perhaps they used a completely different method, which by the way is just as theoretically valid.
Music is results driven, not theory driven. Just as in any langauge, there are many ways to say the same thing. Getting locked into one method as "the way" will cause you to end up speaking like Commander Data on Star Trek TNG.
There is nothing worse than to have to listen to a cat that's supposed to be playing a solo run a bunch of stupid scales with full distortion and pinch harmonics thrown in the mix. As if they're really accomplishing something! :chairfall Improvisation is supposed to be melodic at best or at least interesting at its worst.
So think of modes as patterns that help you stay in the right key in the heat of your improvisation. The same way the pattern of the minor pentatonically derived blues scale helps you stay in the right key when you play the blues. It's only a pattern that you can visualize on the fretboard right? Well then the other modes are just an extension of that. Use them in the same way and not as some Holy Grail. But don't be limited by them. As I stated earlier, their are more possibilities that strictly modal methods fail to yield unless you really open your eyes to the true nature of modes and how they may be used to extend beyond the obvious melodic to harmonic interplay.
For example: A noob might see Emaj chord and think to play a blues scale in E, an E Mixolydian or maybe an E ionian. A little bit smarter cat would say, "Hey! If the E ionian will work then maybe the modes of the E ionian would work as well!". But at this point, they still have not done anything beyond the obvious. A player with yet a little more knowledge and experience would say, "Hey! Emaj is the I chord in E, but it is also the IV chord in B as well as the V chord in A! Maybe the modes of Bmaj and the modes of Amaj would work!". That choice is a little less obvious but not beyond the reach of anyone's imagination that knows some basic music theory.
The challenge comes when we start to recognize the fact that we can choose even more remote modal to harmonic relationships. Thats when we start to see altered intervals like the altered 9ths, 11ths and 13ths popping up. Then more chromaticism starts to be incoporated into ones playing. The aim is not to become pointalistic, however. That is unless you desire to become an abstract player of course. For the most part chromaticism is managed as an element of melodic synthesis in order to create interest while still maintaining a certain level of lyricism.