I believe that it is Malcolm Gladwell in his book, "The Outliers," who investigates the idea that about 10,000 hours of practice is one of the things that allows someone to master his or her calling. In the earlier parts of our photographic journey we have to think harder about the technical aspects of film speed, camera operation, and exposure factors. As we begin to master these things we can spend less time thinking about them and more time thinking of how to express what made us want to photograph something. Or as Bayles and Orland wrote, "art is the visible edge of craft."