tactics, tactics, tactics

One of the challenges for professional programmers trying to advance professionally is simply deciding what to study. We each have a limited amount of time to invest in improving our skills. Should we spend those hours reading about architecture? Computing theory? Lambda calculus? Discrete mathematics? Complexity theory? Compilers? Should we get involved in local user groups, or toy around with new programming languages? Join the IEEE Computer Society? It's easy to find folks who will advocate any of those, and they're probably all correct, in the sense that any of those things help. But we can't study everything, so what is the best place to focus our limited time?

Well, I think I have an answer. But first, a detour into chess.