Let's say each type gets the same rotational force from a dead stop. I believe the low-rg ball will spin faster, dissipate energy faster and stop sooner. The high-rg ball would spin slower, dissipate energy slower and stop later. Each one would release the same amount of energy over time.
In terms of bowlers and real world applications, high-rg balls and are best suited for slower ball speeds, < 45 degrees of rotation, lower axis tilt, medium to drier lane conditions, higher revs or any other factor or combination of circumstances where the ball is subjected to more friction.
Unfortunately, most high-rg balls are targeted at entry level bowlers by having low differentials [very little hook potential], but there are exceptions. The Columbia Freeze Red/Blue for example has a rg of 2.62 and a differential of .047 - which should make for a very hard hitting ball that hooks pretty well in most medium dry to medium oily conditions. I would suggest Med-RG or Low-RG drillings work best for all except very high rev / slower speed.
In other high-rg balls such as the Roto Grip Pantet series, it's best to drill them with stronger layouts for most folks because of low differential numbers - otherwise you might end up with just a nice spare ball or one that you have take a lot of speed off it to make it move.
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Warmon - when all you have is a hammer, everything looks like a nail