The original article spoke of piano. I should have mentioned that the advice I gave is more tailored to polyphonic instruments like the guitar, the piano and th

The original article spoke of piano. I should have mentioned that the advice I gave is more tailored to polyphonic instruments like the guitar, the piano and the accordion. Even on these instruments, the best advice in most cases usually is to practice slowly at first. Just not always. That's what 20 years of teaching the guitar has taught me.