A few points but my info is a few years old now so things may have changed in the epoxy industry I don't know about..


One can use pre-preg uni directional "film" rather than a weave.
The crimping in the weave decreases the carbon strength slightly. So 2 x 100 gm layers of pre-preg will be stronger than 1 x 200 gm weave..

Next is amount of epoxy in the final layup. A good pre-preg will come out around the 40s% epoxy. Straight from the fridge.. A really good laminater will find it hard to get below 60%. Of course one could vac bag and bled the excess epoxy which one could see a 10-15% decrease in epoxy.. This is also true for wet lay build.. Reducing the final epoxy to 30-35% in a pre-preg..
Finally the epoxy in pre-preg is a "stronger" glue than can be easily found in "mix your own" shops.. BUT prepregs require minor cooking (60-100 degrees C) to firstly cure and secondly post cure (80-120).. However wet layups do benefit from cooking and post cure cooking as well.. (gains depends on the brand of epoxy).. Around 60C wet lay-ups starts to get soft.. Sounds like a high temp until you have a black boat sitting in a strong sunny day.. The old wet-layup tubes used on moths were hand deformable after a few hours on the beach..

At the end of the day we are talking minor amounts of weight gain and structural strength.. Its an issue with ultra boats like open 18teens but not an issue with F16s.. There are lots of ways one can decrease the hull weights if one wanted to.. All depends on time and energy one has to expend..
Remembering that vinyl-glass-foam-gel coat "A cats" hit the minimum weight for the class..

hope that helps..
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