I suggest in heavy oil to cross hatch,(not sanding in the same direction of the
flare pattern.Sanding with the track will only complicate things as far as the reaction of the ball is concerned. Imagine a tire with the sipes going in line with the rotation of the ball, The ball would glide wright through the oil( no hydroplane)no hook! But when it hit the back end it would not have the ultimate power to drive the pocket. In another words what I suggested would only imply to a typical lane pattern, what I have noticed talking to other bowlers, the backends rule as far as the ball reaction, also carry down here in the midwest has been torture over the past few years in some houses. You really have to adjust your style, coverstock, and technique to score.