@El Loro posted:A demonstration of a new fire-escape device in 1930:
https://www.youtube.com/watch?v=V6i7rtRRtSM
That clip is silent.
and from 3 years ago:
https://www.youtube.com/watch?v=hrxqorAa8hM
Not too disimilar are they..
I suppose in an emergency one wouldn't hesitate, but in the cold light of day ... I'd want at least two hooks... just incase one fails