From the Mahalonobis Blog:

“if you want to be good at checkers, and you are 7, a good strategy is just not to make mistakes, wait until your opponent makes one, and capitalize. If you are playing a skilled player, you need to develop a strategy that out-anticipates him. In drawing, a good beginner is measured by his realism, but later by his ability to see things no one else sees. Good wrestlers at that age don’t make dumb mistakes, but the better high-school wrestlers are already strategizing: faking moves to open up others.

In the attached picture, Wilfred Dietrich of West Germany (bottom) is actually seconds away from pinning the heaviest man to be in the Olympics (410 pounds), Chris Taylor. You can see it on YouTube. Dietrich supposedly gave Taylor a hello hug at a meeting a few days earlier, in order to see if he could get his arms around him (he could, just barely). Then, he baited Taylor into a double-overhook and used Taylor’s bulk against himself in one of the greatest wrestling moves of all time.

So much teaching has this dichotomy… In statistics, you first learn about basic concepts like means and standard devitions, and move into more complicated econometrics, but eventually you need a nuanced approach that is nothing like what is taught in any textbook–but you need to learn that textbook to get there. Thus a good teacher is often a poor practitioner precisely because he is good at things that work only at a lower level, among true novices. A great practitioner finds these basics boring, and so is bad at teaching them.”