I wouldn't say there are "plenty of stories". I would even go so far as to say that there are few stories of cables spontaneously fraying here on the forums. There are...or were...a few with Shimano's early 10 speed 105 shifters. I've even had to extract a cable from one of them but even that problem isn't the norm. Broken cables just isn't something that comes up all that often.

I volunteer at my local bicycle co-op weekly and I have seen everything that someone can do to a bike and a lot of things I didn't know were possible. Broken cables are an extremely rare occurrence there. But overall, cables seldom fray or are damaged except, as I said above, at the pinch bolt.