All this...
... and nobody really comments on the fact that he basically stopped throwing his splitter in the middle of 2008. That's a pretty big loss in terms of his 'stuff', as I'm sure people remember some of the games over the past few years where he was throwing splits that just fell off the table.
Did anyone think there was any reason for him to change from the FB/SPLIT combination that he had in 07 and the first part of 08? I thought, at the time, that those two pitches could be enough for him to be successful for the rest of his career (a la Rivera with the FB and the CUTTER).
Now, suddenly--and without much fanfare at all--he is throwing occasional sliders and hardly ever throwing a split.
We can talk mechanics all we want, but if Beckett suddenly stopped throwing his curve, or if Oki stopped throwing his okey-dokey changeup would we be discussing mechanics and control, or would we be discussing why he changed the pitches he offers?
I think there is something injury-related. Either the split was one of the reasons that his shoulder supposedly tired at the end of seasons, or they saw weakening and had him stop, or he decided to stop to get that big FA contract in a few years. I don't buy that it wasn't effective (I thought it was one of the best pitches in baseball), or that he was worried that Tek couldn't catch it (there is nothing to support that).
Overall, I would say that Papelbon without his splitter is a MUCH less valuable pitcher than he was with it. He is still an elite closer, but for how long none of us can be sure.