Come on dude. That's ridiculous evidence.
I'm not saying that the pitcher will always get a hit, or even often get a hit - but Stammen is pitching a great game.
I'd rather have him in for another inning or two and let the rest of the lineup try to score some more runs, than pinch hit (admittedly, we've got better bats off the bench than Belliard and Cintron). Especially since Stammen's hitting .250 - he's not Cabrera at the plate.