Looks pretty scary, but i think working at heights is like most things, in as much as you get used to it to the point of complacancy, then you either die or scare yourself into being more careful
I know from working on 4 storey farm house roof for a week you definetley get used to it, i was sh*t scared the first day, but by the end of the week was happy to walk along the ridge rather than crawling and farting with every movement.
i dont suppose the actual height make alot of difference really, just dictates how dead you are. 50 feet....dead 1700feet very dead
certainly wouldnt even want the oportunity to get used to it!