I don't think there's anyone in this rotation that can't use the extra day at this point in the season. We often see Lohse have a start following one of his good ones where he's not as sharp and he fights his way through. An extra day in there occasionally might solve that. Not that he can't win when he's not at his best, but when he is, he can beat just about anyone. When Peralta's fresh, he can be dominating. As for Gallardo, after he short stint on the DL last year, he was revived and pitched very well. As for Estrada, his place in the rotation is shaky at best. Nelson's turn isn't quite lined up with his right now, but a couple off days could solve that. Maybe you end up with Nelson skipping one start to preserve his innings a bit.