In reply to charley:
I've climbed Grim Jim by mistake, thinking it was the regular finish. We were pushing HVS at the time, my mate peeled of the last move, ripped several pieces of gear and landed back next to me at the spike belay. I was pulled clean off of the spike belay and we were both left hanging off a small wire somewhere above.
Terrifying, and newby errors all round really (this was some years ago). We finished it and I remember it being quite a good pitch.