I agree on your first point, but disagree on your second point. Lots of artists use theory-- jazz musicians use the circle of fifths and their knowledge of chor

I agree on your first point, but disagree on your second point. Lots of artists use theory-- jazz musicians use the circle of fifths and their knowledge of chords to give them a framework, from which they can improvise. That means practicing lots of scales, modes, etc, but also practicing licks and such in different keys. If you play saxophone, trumpet, etc.. in a band, you'll probably need theory, since you'll need to do some transposing. Theory without playing music is lifeless, but theory definitely makes things easier to communicate or understand.