Thanks everyone for the responses. It seems that the general consensus is: for good pitchers - using a call bullpen of 1 with appropriate pitch counts is the best strategy. That way your strong pitchers are best positioned to stay in the game until they reach your desired (and effective) pitch counts.
However, it doesn't seem there was a consensus for average to bad SPs (god forbid). If the assumption is that the majority of the bullpen are better pitchers, are y'all suggesting:
1) a higher call bullpen rating, or
2) lower pitch counts with call bullpen=1 (in order to get to pen faster), or
3) both higher call BP and lower pitch counts?
Just curious to know how folks are handling the average to bad SPs ...