AUGH! That's horrible! This was the move that built my back UP after a bad dimmel deadlift rep. Spinal crunch, went numb from the chest down, and fell on the floor. I thought I was through.
I started with bands, gradually working up to a tense band, then the bar, etc...this was 6 months ago. Now I'm hitting 36 inch bent over chain suspended GM's at 251 x 3. If I start to feel it going up wrong, I just back out. Too gun shy...these are nothing to mess around with, that's for sure.