So it's not clear that 10,000 hours is a falsifiable statement.
It not as tightly defined as we'd like, but I think it's still fairly close to falsifiable. For example, I think the Dan Plan is a good experiment. He has a pro golf coach and clearly is doing deliberate practice. It's only one data point, but I think if we get several people like Dan who tend to fall on one side or the other then I think we have strengtened or weakened the theory significantly.