Lox (and others) - you're absolutely right about Django and music, of course. I was just using a little irony in my post to Josepp, but there's water, and then there the backs of ducks.

Having played jazz for some years (I even played a bit last night), I can honestly say that there's no end to the twists and turns in a musical path. But, to get down that path, you have to imbibe - either through the ears or through the eyes or both - knowledge of harmonic progressions and the possibilities within them, and have some idea of the directions you're taking when you go through those progressions. Every note is a decision.

To me, the crucial bit is being able to translate what you hear in your head directly on to the instrument - 40 years later I'm still working on it!