Originally Posted by Boats&Outboards
Shifting up will give quicker take off
Disagree. Longer wheel means higher effective gearing, hence a longer take off.
Shifting down could increase top speed, reducing take off (its a balancing act) but more importantly increasing max RPM so you need to be sure you have the capacity to accommodate a lower pitch.
If you are grossly overpitched to begin with, then the first statement may be true, otherwise probably not. Shorter prop should give a better hole shot, but will hit the max rpm at a theoretically lower speed (though the overpitched thing may come into play here and prove that false.)
Prop should be selected for WOT rpm with a normal load unless you know you have a reason to run differently (always running a heavy or light load, always towing toys, etc.)
My take on things, anyway.