No...but I try to keep my limb tips original thickness out to 6 inches and keep limb with pretty much the same width. Trapping either back or belly is the last thing I do to drop weight. Ten to fifteen pounds glass is all I need to remove. Beyond that some trapping is necessary. On the GM, I trapped the belly down to 6 inches from the tips...but the width on the back was original. What you have to constantly watch is the tiller. After each pass, I flex them through 30" to make sure I have everything even and it doesn't get away from me.
Out of about 50 bows that I've reduced weight, I've had one bow collapse but it was a very unique early Zipper by Bob Thompson...very thin pencil limbs and extremely trapped belly to begin with. I had showed the bow to Bob at Denton years ago. It looked like a kids bow but was 60#. He said he made four of them and the first three broke immediately. Well I thought I could take some weight off the this bow. After my first grinding pass and rechecking the tiller, the bow just collapsed. I should have known better if Bob had so much trouble making it!