When I say standard I am referring to mercurys installation manual where standard is where the cav plate is even with bottom when trimmed parallel. Most sport boats built since '87 { when the mirage propeller was introduced } have them mounted a couple inches higher. When mine was built in '85 the propeller selection was limited. Mercury had the Cleaver and Kiekaffer offered their sport cleaver over hub style. Standard is in effect a cabin cruiser set up. It will work well up to about 60 or 70mph. Once the mirage came out the drives went up. Over time they continue to go up with advances in propeller and hull designs.
Speed masters are surface drives and are different they refer to prop shaft height relative to bottom in the installation charts.

From what I have experienced prop shafts that are in the 4 inch range from the bottom work well for for speeds in the 80 plus mph range. On a bravo the prop shaft is 9'' below cav plate.
This is in general other factors apply. Every boat is different. Different cg's, different notch dimensions, different deadrise, ect .
Singles add the inch in part because the water rises from both sides converging in the center.

Another thing to consider that I see often gets over looked when raising to the limit on twins and triples is the prop height relative to the pad or bottom of V. The last thing you want IMO is to have a situation where the hull is touching the water while the props are clearly still in the air. Boats with 26 degree dead rise and side by side engines and many triples are especially subject to that situation.

Boats that are most fun to operate can skip across the tops without the props spinning completely free.

Last thing to mention is as the boats leave the water there is a moment where the props are still biting and the hull is clear. At that moment you get 100 thrust { provided your still on the throttle } with zero drag. That moment exists as it re enters too. It will lung forward every time it leaves and re enters. Props that are too high relative to the bottom of the running surface will not. Those same boats generally wont carry well and will tend to wet the entire bottom as they re enter. That is why I say a little low in rough water is better then too high every time.

Got carried away.