the bit about not using biners that have been dropped long distances due to unseeable damage being done. This is, for the most part, bogus. Probably in relation to microcracks or whatever...BD did pull testing on biners dropped from el-cap, and found they broke at or above thier rated strength every time unless they had obvious visible damage. From a mtealurgy standpoint, even hardened aluminum is pretty soft, and invisible, hairline, micro, or whatever cracks are darn near impossible to form. The metal will deform prior to cracking, or becomming internally and invisibly damaged to the extent of failure.