What the hell is a "weight program
and what "future" they are talking about? They are talking about the Elan 400 or about future boats? For reducing significantly the boat weight they have to improve building techniques/resins and work on a lighter interior. It is certainly possible since a Pogo 12.50 weights 5.5T and even if I don't believe too much on the announced weight it has at least 1.500kg less than the Elan 400.
But if the boat loss something like 1.5T than the hull should be redesigned to make it more "tendue" and more easier to plan.