tough question! my 81 hulls are hard, they dont give. and i dont stress them, i step very gently on the edges and avoid stepping in the center of the foredecks. i am very careful when testing other people's boats, usually if a hull has a soft spot i can feel it give without too much pressure, maybe 10-20 pounds under the heel of my hand. when i was shopping for my boat i tested dozens of hulls before i found my hard 81. one owner got angry with me when he saw me pressing on the hulls of his boat, better get permission first. i think a hard hull should be able to carry your weight spread evenly on both hands or feet and applied gradually, but i wouldnt do it unless i was pretty sure the boat was hard to begin with because any flexing will further delaminate the hull.