I agree totally about the symptoms of flying a heavy plane. His complaint is that it tip stalls. He says it flys fine when its flying fast. Just because it lands fast shouldn't cause it to "tip stall." My suggestion to raise the leading edge by 1/8th inch will allow the wings too have a little more positive attack angle as the aircraft slows down. Of course you will have to re-trim the plane at high speed. It's my opinion that nothing affects the way an airplane flys more than ....... # 1, wing incidence. and #2 the balance point. I repeat......This is my opinion only.