So, a half ball “reference” alignment and a “pivot” by feel/memory to the actual cut angle.
Right - to me it sounds like “fractional” aiming. They all work similarly.
pj
chgo
The "L" and "R" points change with different head heights.
But as shown they're about at the centerball and quarterball points on the CB's equator, so shooting the CB's "L" at the OB's "R" would be a half ball hit - a 30° cut.
pj
chgo