There's a thread around somewhere about a guy breaking his Speer webbing. I want to say it was right in the middle, but I don't remember for sure. That's the only time I remember hearing of that, which seemed to be the common sentiment.
I've always felt that my biggest enemy is wear, which is one of the reasons I switched to the buckle and ring. My tree huggers (homemade Speer webbing) were mutated all to hell from the line being lashed to them and that was that fat blue Byer rope. Probably had less than fifteen nights on them and they were all smushed and melty looking. Seemed to me like if something was going to fail, that's where it was going to happen.