John,
If you are using a longer lens that has a collar, mounting the monopod to that collar foot solves the problem. I actually put the collar back onto my 70-200 at times when I want to use the monopod to steady things, and I just rotate the camera and lens inside the collar. This is the "normal" way I shoot with the 400 f2.8L IS, as there is little chance of every holding it up for more than a shot or two.
LJ
P.S. This is where that Leaf rotating sensor comes in handy, or the Sinar rotating back. Hoping some of that tech remains or gets spilled over to Phase for folks. For the S2, the issue is going to be using a QR clamp on the RRS part in order to quickly shift from horizontal to vertical, but you still have to unmount and remount the camera.....it is just quicker with the lever release.