I can hardly offer any expert opinion, but do have a few thoughts. Over/under generally indicates that you are a touch high on one shot (maybe best indicated by leaving a four pin), then a touch light on the next shot. It generally happens when you start having carry down issues (i.e. if you bowl on a second shift league after a league where people were throwing plastic balls). Without knowing more about your game and how your ball is drilled it is hard to say. I do know, as an owner of a VG, the following: It needs some head oil or it won't work well even though it is getting into the pocket. On most THS shots, I would not be able to throw it over the second arrow as you seem to be doing. I will also start leaving 10 pins with it if I am not lifting out of the ball properly (arm fully extended, proper lift out of fingers). Overall, on fresh oil, it is a great ball.