Dick:
My guess it its because it can vary so much on the Comp/Arfs. with no ill effects. I have heard weight on the 2.6 from 23 to 30lbs. On the 2.3 from 17 to 22lbs, yet no complaints of heavy wing loading. Of course, you are right. This 2X2 with a DA-50 is going to come out in the 16lbs range which is on the high side for a 78" wingspan. Only time will tell how they fly. With snow on the ground, I am in no hurry to finish mine up.
Paul Eagon