I think it's just a locked Brummel with a very short bury. I think they figure the locked Brummel by itself is much stronger than anyone needs for a bridge so they don't worry about the bury.
I would just look for any sign of slippage. A little slippage probably would not indicate imminent failure because the Brummel would still be intact, but that's when you might want to replace it. The girth hitch of the exposed core fibers shows some wear after a time and it is worth keeping an eye on that as well. How long have you had it?
Sept 2009. The bridge itself looks sturdy. Starting to show wear, like as it's looking a little frayed around the girth hitch and the stitching. But what I've heard is that whatever the core material is it can start to degrade before the outer core shows wear. Supposedly the core material is more abrasive and grinds itself up. Wasn't exactly the warp bridge he was talking about. But in any case...
The bridge has been in my shopping cart at treestuff. So it's on the list and then some. Thanks Moray