David Pinto notes in a post on Baseball Musings that he notices the sort of over-managing in regards to righty-lefty matchups (much obliged for the plug btw, David).
Let’s not also forget it goes both ways. Do hitters sometimes maintain their switch hitting status to their detriment? Do natural lefties who have “taught” themselves to become switch hitters actually do themseves a disservice?
Not Jose Valentin. Not anymore at least. He was a switch hitter. Let’s take a look at his 2002 split stats (BA, OBP, SLG):
As righty: .152, 204, .261
As lefty: .259, .322, .502
In 2003, the difference became more pronounced,
righty: .131, .190, .196
lefty: .265, .345, .535
Jose finally came to the realization that hitting as a righty against left handed pitching when these are the kind of stats you put up wasn’t doing anyone any favors.
So in 2004, Jose renounced his switch hitting ways. He batted exclusively from the left side. While he batted only .216, he did hit 30 homeruns. His .216 batting average may have been due to an adjustment or quite simply, he may have had a down year. I vote for the latter.
What Jose does in 2005 remains to be seen. He has batted from the right side 5 times so far so he may be going back to old ways.