I was under the impression the curved boards were not at all designed intended for full on foiling, rather for a smaller amount of lift to keep it from pitch polling going downwind?
There was a discussion about these curved boards some months ago on the A Cat Forum. I thought they said it was about stability and lift going downwind, not full foiling.
I can't say for sure, but the boards on the A's, M20 and CFR type boats are WELL aft of a boat like the N20. I can't see them adding any lift to the bows.
