No it is not legal because it is underweight. To produce a hull by that means (bagged, vac, cooked,) would have a retail price of about $500.00 and I don't think that anyone is going to pay that for a non-gelcoated hull in the first place, and it becomes even less likely when you can buy a standard wet layup, gelcoat hull that weighs 1-2 ounces more for half that.
When I made them I was not aware that you could turn out a gelcoat hull that light (1 Kg) Now the hulls I am making are coming out at 2 lbs 4 oz. I considered just making the deck... hence the new deck mold, but the deck would be at least $300.00 and again... I don't think that anyone is willing to pay that much for it, so it is a moot point. I can make an 8 oz gelcoat deck that needs about 3 oz of divinicell support pieces inside that works just about as well. (Lacks some inherent strength hence the supports)
I would be interested to know... if anyone has taken the time to weigh the wooden supports and frame structure that is currently being used as well as the weight of the standard balsa/glass deck. I have heard weights on the deck as being around 8 oz.
The 2 underweight hulls were permanently altered into another program that is on long term development.