That's a fair point. A club rider fractured her hip a few years ago, falling off on the Cudham hill descending towards Downe. It's nominally 25%, but she fell on the bit that's much steeper.
Besides this, it's somewhat common for skaters to wear this kind of thing. We expect to fall, more so in a race. It's usual for me to hear 10 or more falls from people right near me during the course of the Berlin marathon. I remember going past/over a girl and the guy from our paceline right in front of me at 25mph on one leg and the other one over the top of them.