I hadn't thought about going with 3 catchers, but I can see a perspective where that makes sense. Having Ross means you can liberally pinch hit and play matchups in-game with Castillo and Montero. Castillo can spell Rizzo for a few games at 1B. The positional flexibility of everyone else on the roster(Valbuena, Baez, Alcantara, & Bryant specifically) means that even with 3 catchers you don't lack for backup options anywhere on the roster. Not my favorite way of roster construction, but it could be workable. We ain't carryn 3 catchers