Seems like if the straps are behind the rear beam you could get into problem with the rudders- would be dangerous if you couldn't bear off the wind in a puff with the spin up. I can just see it- puff with the crew in the straps behind the rear beam and me trying to turn down but can't because his feet are in the way. I suppose this isn't that big of a problem or people wouldn't do it. I guess there is enough clearance between the rudder arm and the deck.

UNLESS, the straps are on the side and not the top. My 6.0 had straps when I bought it- and I replaced them with nicer ones but they are more mounted on the top than the sides.