An awful lot of performance involves skills that are NOT addressed by music theory -- basically everything that distinguishes a mechanical MIDI performance of s

An awful lot of performance involves skills that are NOT addressed by music theory -- basically everything that distinguishes a mechanical MIDI performance of some piece from an real performance by a professional is not part of foundational music theory. There's also a great deal of ground that music theory formalizes that long-time musicians will grasp intuitively (but be less able to discuss, of course). Just some complementary points.