When your bullpen is THIS much better than your starters, time to maybe look at your rotation and your bullpen and see who can be swapped.
Problem with that is most of the former starters in the pen are much better as relievers. Stammen, Balester, Clippard, and Burnett are clearly better in the pen. Detwiler is just there in a numbers game right now. Olsen can't seem to find enough health/consistency to stay in the rotation.
JZ looks like velocity is back and control is iffy right now. He's had a couple of good starts, a really good start, and a couple of bad ones. I would expect that to be worked out by spring training once he's had time to do enough throwing to get the feel for all his pitches all the way back. The other 4 in the rotation should be told to pitch lights out the rest of the way or risk being replaced if the right deal comes along.