1. A higher value finish produces a smoother surface. This surface produce more contact with the lane surface. Which means, it skids more in oil and moves more in dry.
2. Lowering the surface then has the opposite effect by providing room for the surface to bite through the oil and touch the lane surface in the oil (which can cause it to grab more through the oil) but becuase less surface in the dry it moves less on the back.
3. Polishing has the effect of producing more skid in the oil.
So, reducing the surface and then polishing would cause the ball to get more midlane roll (by allowing the surface to cut through the oil) but maintain more back end without polishing.
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