In college, unless you are a standout, it is very hard to really concentrate on both. I think that some have the personality for pitchers and others personality for position players. I was quite surprised to find out that two of the outstanding fielders were pitchers in HS, good ones, but had awesome bats and therefore were prepared for college as position players only.
Something does suffer along the way for two way players.
Pitchers know their role and accept it.
Pitchers at CU were told if they won regionals they got to do batting practice for one day, that's all the talked the night before, how they were going to "smoke" the ball, and the coaches would be so surprised! Yeah right!