Ivy League to MLB has an interesting post today on the psychology effects of bullpen role definitions. I agree with this concept, but not necessarily the conclusion. I wrote about this earlier in the season, and respond in the comments:
The problem isn't that bullpen guys have defined roles; it is how those roles_________________________
are defined. I think that a bullpen coach who is actively engaged and
effectively communicates with the pitching staff could easily get a 'pen
prepared for non-closer centric decision making.