Chi...great points. I thought the going fingers over the bridge for you on a High RG Arsenal Reactive would definitely help you get the ball to "push" a little further down lane before making its' move.
hotshot187, my PAP is 5 1/2> 5/8^. So we're pretty close. I have a Slash that is drilled with Pin directly under my bridge with the pin kicked right on my midline. It's not a high flaring ball, so I track right over the edge of the thumb if I stay right behind the ball. I barely clip the thumb, so I'm thinking you should be ok. My Delta is drilled Pin under bridge too, but with it being a Strong Asymmetrical Reactive ball, the track migrates and flares a bunch away from the thumb (At minimum 1" away from thumb) Hope this helps and wait for some of the other staffers and bowlers here to chime in!
Regards,
The Rawmull Bull
--------------------
"Heck Yes!" Napoleon Dynamite