The rivalry between the Yankees and the Boston Red Sox may be the most overhyped in sports right now—Alex Rodriguez was a first-year Yankee, and Pedro Martinez was still in his late prime, the last time the clubs met in a playoff game—but you'd have to be awfully cynical not to get even a secret kick from it.

Nine hour games, fake controversies, obscure grievances and all, a Yanks-Sox doubleheader at Fenway in July is exactly what you'd inflict on a foreigner who wanted to know about America's curious...