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There have been many questions about this drilling and the purpose of the layout. First of all this drilling happens to be nothing new. We have used it to reverse the flare for Full-Roller releases for quite some time. This layout allows the flare to move away from the fingers instead of towards them. Using it for non Full-Rollers is the only unique aspect of the layout.
We have always liked the different move this layout makes to friction. The move is less lateral, meaning the ball seems to make a more forward move down lane rather than a sideways move. Due to this we use this layout when we want to see particular bowlers use less angle through the front part of the lane. We have also observed a different move through the pins than that of positive axis layouts. When we want to reduce the move through the pins we have had success using this layout.
Because of the arc shape difference we have been able to attack the higher friction boards from a different angle. It has been successful when we see a bowlers head and belly not matching up. You can hook this layout, but when you are over projecting this layout your carry will suffer. The biggest challenge when using this layout is the transition moves a bowler needs to use.
Parallel moves work better than typical 2 and 1's. Speed is also an advantage when using this layout. Just because the ball sees early friction a bowler can not be tempted to move too quickly. Throwing it harder and maintaining lesser angles through the front part of the lane are advisable.
For those that wish to experiment with this layout. You will need to be very selective with the pin to CG distance. We start with the longest pin to CG distance we can with a minimum of 4 1/2 to 5 inches (this is very relative to the length of the bowlers span). Static weights are a concern and using the depth of the fingers and thumb will help keep the ball within legal limits of ball specifications.
Reversing the flare will in many cases cause the track to flare over the thumb hole. To avoid this you need to lower the pin placement. The theory by Ray Edwards in the R & D department at Brunswick is to draw a line between the pin and the positive axis point. This line needs to be 1 1/2 inches beneath the backside of the thumb hole.