So, is the consensus that you CAN build a 20' too light?
I don't think so. The CFR is 245lbs at 8.5' wide and 24m^2 on a M20 mast. It needs more weight to make it go, so you can't sail it light, but with 375+ on board it FLIES! Light in the platform and rig means we can (and have to) carry the weight where it matters but it pays off.