Coming in todays game Derek Jeter is batting .310
He is 2 for 2 so far so he goes up to .314 (((((((((((((

))))))))))))
He is right on his career average at that point.
so according to bankrabber, Jeter is not underperforming at this point because hes average is right on his career average .314 since he only considers good all star season for Jeter if hes average is at career average or higher.
EDIT:
Update... he just grounded out so he now 2 for 3 ((((((((((((

))))))))))))
so hes average dropes one point at .313
so now hes back to his 'underperfoming' wagon.
lets wait and see what he does on his next at bat, hopefully he gets a hit and raises up to .314 again and we be all happy again. but wait, we still got over a month baseball to play.. so Jeter gonna be jumpin on his 'all star' to 'underperforming' wagon back and forth every game.