Been thinking about this topic leading up to the race.
I read through this fellow's blog re tethers and jacklines. Some very interesting thoughts especially with regard to point loading and fall arrest.
http://sail-delmarva.blogspot.com/20...hulls-and.html
I was at REI over the weekend buying a climbing harness as a safety backup to my top climber for ascending the mast. I have a round spar on the Freedom so I can use a kleimheist around the mast and attached to the harness as backup fall protection. While I was there the sales guy introduced me to the climbing wall and suggested I try the harness out. Wow, that was an interesting experience, just to feel my 200Lbs (OK, maybe a little more) suspended from the wall. Going upside down and generally goosing about in the harness. It was exhausting after just a few moments. I plan to return with my sailing harness just to find out what it would feel like to be dangling over the side. How much mobility I would have, etc.
This kind of experience is what I thought was so valuable about the safety at sea training. You actually got to use your gear and, in some cases, it was not pretty. At least you know ahead of time it isn't going to be pretty and are more or less psychologically prepared for it.
Bottom line is you don't want to be over the side. I am shortening my tethers accordingly.