I would like to hear more from folks who have experienced the same issue. That string loop is padded to a fairly thick end loop. The thick end loop should help prevent the limb split. Is it actually caused by the ff material under normal use or a dry fire with ff material? Also does this happen more with wide versus thin limbs? How about recurve vs longbows & wide vs thick limbs for each? I would never shoot a ff string on a bow that is not rated for it. The problem is that this decision is presently based on conjecture and second hand info. I would love to know what actually causes the problem. Bowyers, and people who have experienced similar failures please weigh in here.