Macca like yourself, compared to some on this forum I know very little, what I do know is that a dagger board is simply built in a process which is no different whether it is curved or not.

Yes you are correct, there will be additional loads requiring additional layers of strengthening fibres, but those fibres will cost little in the comparison to the materials over all costs. I'm talking 10's of dollars rather than 100's.

The highest cost of these type of products is the R & D but over a volume product then most of these costs can be absorbed into quite small numbers per item produced.

Its time we took the ohhhh factor out of curved boards, they have been around a very long time ( the very early Farriers had them way back in the 80's ) and got on with the job of learning how to sail with them as one thing for certain, the marketing boys and girls have them in their sights as the next holy grail and will push them hard in the next few years, what ever their worth.

As I have said before, I will reserve judgement on their worth until classes such as the A class, where the light weight of the platform should enhance this type of structures useage, have firmly come on side.