Hi Stephen,
I`m no rock star, but just curious as to how much performance there really is in 5kg. As a percentage of the overall boat weight, it represents 4,67% of the boat weight, does this make it 4,67% faster ? If it did, all the top sailors would drill holes all over the decks of their boats, and make sure they don`t capsize.
If you take the F16 specs and punch them into the ISAF rating calculator, you might find a 1% gain (tell me if it`s more, I am a bored insomniac, but not THAT bored.) If I`m right, that`s a 36 second advantage in a 1hour race. Now at weekend-warrior levels it MIGHT get noticed, but if your opposition can sail half a degree higher than you can on a 5kg heavier boat, I`d guess it would be a fair fight.
My guess is having all the boats at min. weight with correctors would attract all the rock stars and the big manufacturers, a sure way to kill a class if ever I`ve seen one.