Coriolis, the French mathematician, described this masse aiming technique. The essential principle is to elevate the cue until your tip points down through the CB at an imaginary line on the table drawn from the CB's base forward and parallel to the path you want the CB to take after curving. The "compass" direction you point the cue determines the CB's initial direction. How hard you hit the CB determines how far it goes in that initial direction before completing the curve onto the parallel path.
It's the best masse aiming technique I know, it's very accurate with some practice, and it works on all masse shots from small shallow curves to 180-degree "turnaround" curves.
pj
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