The thing about Point of View cameras is that if the user does something terrifying, it also scares the wits out of the viewer!
There really isn't much to say about this, except that you really, really shouldn't watch it if you have a phobia about falling off high places.
Watching footage like this gives you the best possible insight into the sort of person who would take massive risks for pleasure. And about us: we'd rather watch it from the safety of our desks!