Quote Tony Raven:
For creatives, ANY widening of experience is a good thing.
Last week I was chatting with a friend, another guitarist. He happened to mention that his band was going through Hell trying to cover a couple of Soundgarden tunes. Without thinking, I said, "Oh, the ones in drop-D, right?"
He had no idea what I was talking about. So I took a literal minute telling him to downtune his E & barre across the bottom three strings for those aggressive chords.
Next week, Black Sabbath.
I can vaguely understand a few spoken languages, but staves have defied me for 40 years. Yet I am a strong learner via visuals, so YouTube has been quite a blessing for me. If someone plugs in & SHOWS me how a riff goes, I can usually pick it up after a half-dozen flying starts. And if said someone gives me an explanation of what I've done AFTER I get a grip on it, theory makes much more sense. Telling me beforehand usually just adds to the initial confusion, a variant of "the centipede's dilemma."
Sorry - me again, just noticed your comment - YES, theory in a vacuum means nothing. Saying to someone "here's 7 modes, in all 12 keys, that's 84 scales to learn, then we'll start on the dimished's and augmented's the altered's etc... at the end of all that you'll be a musician" - is worthless. It has to be learned on the go. I was lucky that my teachers at school (one in particular was a total genius, I owe him the lot really) went through the lot in minute detail, but with listening to music all along, so you could see all the principles actually played out in real music rather than learning theory "in theory".
To some extent though you have to start at the beginning - I teach once in a blue moon now, but I try to point out stuff that's happening in real music, preferably something the pupil's into, but they rarely hear it because we haven't started at the beginning, done any ear training or basic harmony.
A classic comment from a punter on a blues weekend workshop - he wanted to learn some guitar licks and was impressed by my guitar doodlings (my guitar playing is at stoned-student level), so I made the fatal mistake of mentioning pentatonic scales - he came out with a stunner - "don't blind me with f***ing science, just show me how to play like Eric Clapton"!