Comment by rdl

I don't know how big a deal the harness really is. Even getting out of a helicopter underwater with a regular 4 or 5 point harness with a single-point twist buckle after a crash, especially if the vehicle isn't perfectly vertical, if there's debris or gear inside, etc. is going to be very difficult for anyone who hasn't trained in it. The military has simulators (https://www.youtube.com/watch?v=POsWGHfHg4M) which are way simplified over a real crash, and even that is hard for basically professionals in peak fitness.