Nah, but I grew up around a lot of people who did, thought I probably remember what a girth actually is from climbing, where you often use a knot called a girth hitch (which far as I can tell no modern saddle uses). Well, actually you use it as little as possible, but you still do.

We use what's basically a 3x larger version of what nylon straps are made of in climbing and trust our lives (or yours if you're a hiker or something and we're rescuing your a**) to it all the time; granted we usually don't subject it to toothed buckles (and when we do we carry a spare). My experience is that nylon straps mostly go out because of the crappy ways in which they're attached to the buckle, though you can occasionally wear through them where the other end goes through the buckle. I get better results with the stiff flat webbing ones than the floppier tubular webbing ones, but who knows, it's not like I've been at this 50 years and have worn out a gross of everything on the market.