Your centre of effort of the sail is consistant with a 3.90 mtr luffed sail on the F12. That would give the boat a 5 sq. mtr. sailarea if the minimal required aspect ratio is 3
Again Wouter you are talking about your design not mine, as I have said all along I would use a 7m2 windsurfing rig on a 460 mast. The gust response of these sails is very good I would not expect to see the situation you describe.
This is a similar rig to that used on the international moth that won the world championship a few years back so perfromance is not as bad as you are trying so hard to make out.
