2 friends and I went and ran SGR Slot outside moab last Sunday (11/13/2016). The third rappel is 75 feet into a large silo. We elected to stem out about 15 feet past a section of narrows that looked difficult to rappel down to where the canyon widened out. On the way down, my buddy noticed a rope stuck around a chockstone about halfway down the rappel. He had already passed the chockstone, so I rappelled down onto the chockstone to unstick the rope. It became obvious that when pulling the rope, the tail end had fallen on the opposite side of the chockstone, becoming wedged and forcing the previous party to cut their rope. We discussed how to prevent befalling the same fate, and elected to pull the rope from a certain spot, where we felt we could pull in such a way that it would prevent the rope from getting caught on the chockstone. We were wrong. Our rope did exactly the same thing as the previous party's, and after a short attempt at pulling it down, we had to cut the rope. Thankfully we had the previous party's rope and were able to complete the canyon using that as a pullcord, however if we were without that rope we would have had to bail out of the canyon at some point and endure complicated navigation back to our vehicle. SO...if you're going to run SGR Slot, be warned on the 3rd rappel. Some ingenuity would be required to prevent the rope from getting stuck on that chockstone.