According to a study done with violin players, highly structured practice is what separates the great from the very-good. Those that were very good but didn't p

According to a study done with violin players, highly structured practice is what separates the great from the very-good. Those that were very good but didn't practice as much ended up becoming violin teachers: http://imgur.com/Wxjqa.png http://imgur.com/Wxjqa.png. What's also striking is that amateurs practice far, far less than the best: http://imgur.com/vIB6i.png http://imgur.com/vIB6i.png. While they may have practiced for the same number of years (e.g., from 4 years old to 20 years old), the amount per day was substantially less. This is from "The Role of Deliberate Practice in the Acquisition of Expert Performance": http://projects.ict.usc.edu/itw/gel/EricssonDeliberatePracticePR93.pdf http://projects.ict.usc.edu/itw/gel/EricssonDeliberatePracti..., pages 17 and 21, respectively.