Remember Dave, that kid who got really tall fast, who towered over everyone in Mrs. Ambrozewski’s third-grade class? His height advantage persisted through fifth grade, but the gap started to narrow as other kids hit puberty in middle school. Dave remained the tallest kid, anchored the basketball team, was still the go-to guy when Sister Irene needed someone to reach something on a high shelf. But instead of being head-shoulders-and-chest above everyone else, he now had only two inches on the next-tallest kids. That was still a considerable advantage in gym class, but it didn’t lend itself to domination.