Originally Posted by Trajinous
I disagree completely on this one. It's the catcher that suggests the pitches to the pitcher. The ability to have that communication is vital to successful pitchers.
By having the same catcher, they learn each other's little quirks like knowing when to block a curveball in the dirt. I think it helps continuity and creates a routine. Every pitcher I heard speak emphasizes the importance of a routine when starting. Changing the catcher could disrupt this and lead to mistakes like passed balls or pitch select disagreements.
They can talk all they want. When they change teams or a catcher goes down, they somehow figure out a way to pitch exactly as expected almost without fail.