Interesting to consider, though not discussed much in the article: quality of practice is paramount. Thoughtful and deliberate generates incremental progress. Casual, mentally checked-out practice isn't practice at all. Some discussion & sources here: http://ideas.time.com/2012/01/25/the-myth-of-practice-makes-...

One mantra tossed around of late is "_perfect_ practice makes perfect," meaning not to never make mistakes, but to be conscious and analytical when you do.