Carl, is your argument that the funky way our boats were put together actually is the reason they lasted so long?

I hadn't thought of it in that manner, but, yes to a degree. In my introductory work on 259, I find no part of the boat where the workmanship stands out as skilled joinery. The balsa under the mast step was a mistake but look how long that lasted! The cabin door is missing on 259 ,may have started to drag and was removed. When I check the squareness of the opening, it was still square.
Creating a super stiff section with no flex I don't think lessens the force, I would think it transfers the force and maybe even multiplys it to the weaker non-reinforced area, at least in the case of the truck frame.
Not having bulkheads fit perfectly to the hull and glued solidly helped to eliminate hard spots in the hull.
To look at any part of the construction of these great boats and say not done good enough really has been proved wrong by time. IMHO
Can you think of anything built in the 60's that has been used, abused and neglected and still be brought back to as good or better than new for less than the original purchase without adjusting for inflation?