Well James, your first clue should have been "Great Planes". I think the correct term is oxy-moron. For instance, I got a kit of their 60 sized "Stick". One of the major design flaws was in the fuselage. The fuselage has ply doublers that stop just short of the firewall. So instead of having a plywood to plywood joint which is fairly strong on the fuselage sides, you have the firewall glued to balsa fuselage sides, butting up to the plywood doubler. Just dumb design. Of course this is in a kit that featured 18 pound balsa in the wing ribs. This was impressive, since I had never seen wood above 12 pound stock. It will handle the Kansas wind.

As to shear webs, most models are overdesigned. One kit design used 1/8" square sticks in an X pattern to act as shear webs between ribs. The ribs should provide enough compression resistance for most sport models, even though the grain is wrong.