There's a difference in having guys who come off the bench here and there to spell someone a day off or PH now and then, and being depth to fill a position spot for a week(s) or month because of an injury.
Those guys are not ones you want filling in everyday and getting 20+ AB a week because of an injury to a starter, cause the more they play everyday the more you see their weaknesses.
Everyone keeps bringing up Tauchman OBP, he hasn't been bad lately, but realize his OBP was actually at .500 11 days ago because he was walked 8 times in his first 8 games, he has 1 walk since (11 games) and as we see his OBP has dropped significantly. I'm not thrashing Tauchman, but he's not a guy you want to give AB to everyday like they have been giving him between OF and DH, 2 starts a week is good for him as a 4th OFer.