The first thing to remember here is that we are dealing with the same organization that told us that short oil would reduce high scores; it didn't. Then we were told that 3 units of oil on outer boards would reduce scoring; it didn't. Then we were told that increasing the weight of pins would reduce scoring; it did for seniors and children, but not for anyone else.
The problem is that the USBC believes that an extra hole makes one a better bowler; it doesn't.
As a proshop operator, extra holes are invaluable for fine tuning ball reaction.
The placement of the cg, in and of itself, does not significantly alter ball reaction without an accompanying weight hole. A cg can be placed far from the center of the grip without an extra hole, if the starting top weight was low. This ball and one with the cg in the palm would both react very similarly, provided the pin placements were the same. A weight hole, added to a low flaring ball, in a position that increases flare, will show a greater change than that of a high flaring ball. Today, with balls having large differentials, the weight hole becomes important for reducing flare. What very few people realize is that leverage drillings on high flaring balls create a "sloppy" flare pattern at the pivot point. By reducing the amount of flare, either through pin placement or extra hole, the pivot point becomes cleaner and the back end reaction more crisp. Finally, cg placement on mass bias balls is completely irrelevant. This statement is supported not only by Brunswick, but also by Mo Pinel, even when his equipment was being manufactured by Columbia, and also supported by Del Warren of Track.
