How much can you furl a headsail
I think that Rich hit the nail on the head. You can only expect to be able to furl 10% to 15% without a foam luff and beable to get a decent shape and then only for a short time. Over time the rolled in luff and leech creep toward each other powering up the sail (making the sail shape rounder) just when you want flat sails. I think Rich''s 30% may be a bit on the high side but even so at the shape of the sail at that range is not what you would want to get home on in a blow.