Ok, my bad, but I just looked at that Hoyt arrangement. Ooops. But, that line that runs forward from the clew is the outhaul. All it does, (or should be doing), is tightening the foot of the sail. In heavier air, you would want it tight, to flatten the sail area. Conversely, it should be more loose in lighter winds for more belly in the sail. But I can see now why it would slam in a jibe. Without looking at the actual diagram, I assumed it would have a single block in the middle. Wrong. This slamming could be controlled with a preventer, by adding another block on each side, running a line to the end of the boom left and right.
(Notice how I avoided that whole port and stbrd thing). Then run those lines back to the cockpit so that you could slowly pay it out if you jibe. I would almost be inclined to put a single block at center, and just avoid the whole mess, but maybe that sheeting setup provides a better tensioning of the leech. Still, if you pull that jib sheet down very tight before you jibe, it may take some of the shock out of it, but the preventer is sure enough going to do it. I'd keep the end of the preventer line in a clam cleat though, getting rid of it before a broach will be a lot less sphincter tightening..
