My brother and I did Leatherman, Badrock, Church, and Donaldson in a day. Did not actually do "the spine" but dropped down a bit (see picture). It was mostly 3rd and 4th class with a little 5th class descending from the summit of Bad Rock and on the N.Face Church. We dropped completely off the ridge to do the aforementioned N. Face Church route after we ran out of water and saw some far below. I doubt anyone has actually ever stayed "on the spine" because it is pretty rotten and would take forever if done roped up. It looks interesting doing Church from the Badrock saddle, but we did not do it. Best of luck!