I agree w/Valen and others who feel this way. There's no way I'm using an $8 mill pitcher for mop up work. The worst thing that can happen (IMHO) is to burn 4 innings when my team is losing 9-2. Let's say I make a game of it and lose 9-7, but Babe is cooked for the next game. That next game I'm up 7-5 and I'm forced to use bottom of the barrel pitchers and lose another game when those pitchers give up 4 runs in a loss.
I'd rather use his innings to shut down my opponent in a tight game or when I have the lead. Most innings isn't the goal for me, most QUALITY innings is.