Len, it's a totally legitimate issue. I've got a tallish/slim skeleton, maybe from genes, probably from crappy childhood nutrition. Some muscles like adductors and lats actually get in the way. Having a manly transversus is downright uncomfortable. Find your limits, then retreat to wherever you feel healthy. At 6'2" and 210ish I got a perfect double clean and front squat with a pair of 40 kg bells. It was just too much, and my guts hurt. So, I'm resigned to mediocre numbers -- 405 deadlift, 10 x 10 swings with a 32 kg, backsquats with 225. As a consolation prize, if I can't have Paul Anderson type strength, at least I have above-average talent for jogging.
Also, keep the reps low - see any of Pavel's writing.