...did I just discover something cool? I was fiddling around with the keeper on my French Navy commando issued DW-9000, when I happened to line up the slot in the keeper with the groove separating the G on the tail piece from the rest of the strap. I've never considered this before but the slot in the keeper when lined up with that groove in the strap acts like protector, since the groove is the weak point. That point in the groove would be the first thing to split if the strap somehow got snagged on something.
I'm probably just hallucinating but if you think about it the theory holds some water. It's actually possible to line up the edge of the slot and the edge of the groove perfectly, so all you see is the groove. I just photographed it that way so you could better see the groove and how the slot lines up..interesting..