It would be ungracious of me not to accept the kind words. Thank you! Perhaps I should have relied on Bird's old request that "polite applause will suffice"!
As to helping with playing, some of it has helped hugely - note lengths, rests, time signatures and key signatures (you have to know all 12 majors plus minors in melodic and harmonic form). Knowledge of intervals and basic triad chord structures and their use on I, II, IV and V and transposition at octave, 2nd 3rd, 5th. It is more classical based though than jazz, so at that level there is nothing about blues, modal or pentatonic scales, or 7th or further extended chords. There is also stuff on the capabilities of all the standard classical orchestral instruments, plus writing in bass clef .. oh and alto and tenor clefs! So it's not all imediately stuff you need if you're a single instrument player, but if you like to know the underlying theory of things, as I do, then it's good to do. But I can see not everyone would want to.
Re what's next, not sure about composition yet, and anyway that's where I dropped marks this time. Up for Chris' suggestion though. Anything for a bit of subatomic particle physics research that might lead to the Grand Unified Theory. Actually I've been toying with the idea of using the London Underground Circle Line as a particle accelerator, with the Olympia branch as a Hadron collider. Slight worry about whether any Higgs' Bosons would pass harmlessly through stray commuters or cause them to spontaneously combust, but we'll see.:shocked: Any one join me?
Colin