With respect to every decision made, there are good ones and bad ones (and relatively inconsequential ones). Numbers and probabilities are our best bet at figuring out which ones are which. What the hell else is there? Managerial instinct, the traditionalists say. "I saw so-and-so hit well in the cage today despite his recent struggles and I will pinch-hit him in the 8th." I don't buy that there is a psychology and sociology to the game, things we haven't figured out yet that influence how players think, but I think it's possible and one day it could be quantifiable.