You know, the internal skeleton idea, that is exactly how a WilderNest is built... There is a molded in steel frame that is pretty strong and does not flex much normally. In fact it only deflects about two inches when it must hold up the weight of a truck, so a few hundred lbs is no prob.
'91 Toyota Pickup
'09 Kawasaki KLR650
'12 Gunnar Rockhound 29
“Anyone who believes in indefinite growth in anything physical, on a physically finite planet, is either mad or an economist.” -- Kenneth E. Boulding