I spent about 15 years in an industry working at these heights... it's funny I never looked at it that way until I was talking with a friend of mine who's a cop trying to figure out who had the more dangerous job.

It wan't a dick measuring contest, we were honestly just trying to figure it out. And that's when I realized it's exactly how you put it... not that dangerous a job really but at the same time you are always just one slip or minor error away from instant death for 50-60 hours per week.

There's a bell curve of danger doing work like this... at first it's dangerous because you're scared and not thinking straight. Then it's safer because you learn how to handle it but are still very vigilant. Then it's dangerous again because you're too comfortable with it, and aren't as careful.