I was taught by the marina I worked for years ago to prop for a light load, then you would be good with a heavy load. Prop for max wot with a light load or even slightly above. You will need to watch your fact with the lightest of loads, but it always worked well even with heavy loads. If towing or excessive load/ weight then an extra lower pitch prop might be needed. This method has never failed to make great performance in all the years I have used it. However, each to his own...your boat, your motor.....
