Why is the "anomaly" below difficult to explain? The bat doesn't swing on a hinge at the end of the bat. It swings on the shoulders of the batter.
Bret Cahill
"The sweet spot on a baseball bat is generally defined as the point at which the impact feels best to the batter (it is also occasionally defined as the point at which the maximum velocity is imparted to the ball, but this may not be the same point).
"Although it has long been believed the center of percussion and the sweet spot are the same, recent practical observations have indicated that the point many batters feel is "sweetest" corresponds to a pivot point not in the handle of the bat but beyond the end of the bat. [citation needed] The reality of, and explanation for, this anomaly are currently areas of active research."
-- Wikipedia