In reply to beardy mike:
> In the case of the standard Bulletproof the point is that many biners are left on sport projects where stripping gar for each attempt is no the done thing, leaving thousands of biners out there which are slowly but surely wearing through and producing said razor sharp edges on aluminium biners.
I thought it just wore the krab and made it thinner where the rope rubs. Not the same as my example. Same thing applies re gates on perma-draws, they will be knackered if left out long before the krab wears out. Also the sling will be the weaker link in this case I would have thought?
In the case of the HMS, it's simply there to protect the wear surface, especially when used with some autolocking belay devices which tend to concentrate all the wear in one area. I'm not sure why having an extra margin of safety would be a problem...
Well I've given an example, and the USP is not an extra margin of safety, as I don't think that is required. The USP is to add longevity to the krab, which I don't think is required (or achieved) either.
Andy
Post edited at 14:43