I wish I had a picture of their boat, a very modest but very well outfitted "classic plastic" Ontario 32. They'd run a piece of wide nylon webbing from the stern cleats forward and up to the shrouds, where it was looped and somehow secured one one of them --by a hitch or something, I couldn't tell and I don't have a pic of their boat-- and then forward to be secured to the bow cleats. They said it was also very, very useful to use as a handhold/balance point when going forward, i.e., to have something higher than the lifelines to grab, which are a bit low...the high jackline also might prevent you from falling overboard since it's high, and would catch your body at a point higher than the boat's lifelines...they "swore" by this arrangement...just as strongly, no doubt, as others swear by jacklines on the deck instead! I'm intrigued the having them up high...I'd like to experiment with it.

But good point about the jacklines being attached to the rigging, which would likely give way in the event of a roller over...however unlikely a rollover is...there's always a tradeoff to make somewhere!