Thinking that merely "overpropping" by some amount is a simple solution is ill advised. Of course, if you go over to a much more authoritative forum such as Boat Diesel, you can begin to understand (and be forced to argue about in an informed fashion) that the prop is only part of the equation, to get the desired result outside of the box defined by the boat's original drive train set up. Working back up the system, shafting, reduction gears and engine tuning all come into play.
Mere over propping is a recipe for shortened engine life. It puts stress on the engine all the way through the power curve. Guys try it a lot to get better "hole shot" acceleration out of their outboard boat, or more speed out of their big sportfisherman as well as yes, better "bite" at lower speeds for fish-on-the-line maneuvers.
So if you want to really learn and converse about this issue, go over to Boat Diesel, and/or get yourself a copy of Dave Gerr's "The Propellor Handbook".
Same applies to the "Underloading"thread too.
Many of us have Gerr's Prop handbook. Gerr's "The Nature of Boats" actually does a better job addressing the manner in which the other driveline components enter the mix.
Putting additional stress (load) on the engine is one of the payoffs...FF has been making this point for years. Sure, the other drivetrain components should be addressed in any analysis, although I'd bet dollars to donuts that lots of boats came out of Far East factories with no testing or analysis.
Prop efficiency discussions are all over the internet. Boat diesel members have great maintenance expertise. Engineering expertise maybe not so much.
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