[jacobolus]

By the same token, if you need a computer to draw [this or that] so what? Or for that matter, if you need to hire a trained draftsperson to do it, so what?

> Most people can accurately trace a line drawing, but can't accurately copy it by eye.

Yes, tracing a line drawing has much more direct feedback. The correct line is right there, and there is no need to synchronize imagination with hand movements. (Untrained people are still very slow and error-prone at tracing though, compared to professionals.)

In a similar way, people have an easier time playing a piano tune if you directly show them which notes to play on a physical piano a few at a time right before they press the keys themselves vs. if you let them hear a whole tune and then try to play it from memory a few minutes afterward.

That doesn’t make piano playing an “almost entirely audial skill, with almost trivial mechanical skills” involved.

[lmm]

> That doesn’t make piano playing an “almost entirely audial skill, with almost trivial mechanical skills” involved.

I'd say it does. I have terrible hand-eye coordination but can play piano at a decent level (whereas I'm distinctly bad at e.g. tennis). Playing a piece I already know on the violin on the piano (or vice versa) is a much simpler exercise than learning a new piece from scratch.