Re: Joe Posnanski with more data showing that closers simply don't matter
I think the use of a closer has become commonplace in order to shield the manager from criticism. If the manager goes by the book and uses his relievers according to a standardized formula and the game gets blown he can just say "Look, I did everything by the book and it still didn't work. The pitcher blew the game, not me."
If the manager mixes and matches his relievers on a daily basis he opens himself up to criticism from the peanut gallery whenever something goes wrong. Sportswriters and armchair experts would be second-guessing and Monday-morning-quarterbacking his every move and blaming him instead of the pitchers for the losses.