Billy Beane is constantly attacked for destroying the looker room chemistry in the local press.

True, only if you have a great team already and you don't desire messing it up. If that is the case, you wouldn't need that method at the first place.

On the other hand, teams are pretty dynamic these days given the interfaces and responsibilities are well defined. Or at least are largely defined well. So replacing team members is never really a problem.

- You can't always predict the future about a given player's performance.

- We're still arguing about what the right measures actually are (although there's more data all the time)

- There clearly are sometimes cases where personalities and attitude mean some player needs to leave even if his historical stats were good.