This is a long and thorough piece, not a quick read, but it's fascinating, has some great little tidbits, and kept me reading until the end. It also never gets simple or condescending.
One small pullquote:
Being smart, having a “killer instinct” (or whatever your preferred cliché might be), and putting the necessary hours into practice may not be enough. In addition, chess excellence may require a particular thinking style—a way of processing information. There are plenty of smart people who attack chess with great gusto from an early age, but never get past an intermediate level. In some cases, it may be because they can’t quite match the competition in some of the cognitive skills that would give them an edge, such as the ability to recognize and recall patterns, visualize and analyze options on a two-dimensional grid, and make decisions that balance multiple strategic considerations. Spatial ability, the subject of my own dissertation research at Harvard University, may be particularly important for success in chess. The lower ranks of FIDE’s lists, therefore, may be littered with chess enthusiasts who are destined to play out their careers in obscurity because they struggle to develop the particular kinds of cognitive skills that elite chess demands.