FYI, "aiming to make the contact points collide" is done "by feel", just like all aiming methods. Starting with a known visible "reference" alignment like "fractions" doesn't change that. Even if the shot is an exact fractional alignment (needing no adjustments) you only know that because you've learned to recognize it "by feel".And that is also exactly my point--"you are aiming to make the contact points collide" is different than "focusing specifically on the thru the center of the cue ball aim line". When using a 'fractional system' aim line, the focus IS on the CCB aim line, so when shifting to joining the contact points, one is now "aiming" with a line that is parallel to the CCB.
Imagine this...If I put you in a pickup truck, and placed a basketball on a pole (wide enough for the ball to sit upon), and instructed you to knock the ball off with the passenger sideview mirror, you would not be driving straight at the pole--neither to hit it center-grill, nor in front of the driver. In this case, you would be "aiming" with the mirror, and not the centerline of the truck/driver. Now, you could also say that you are "aiming" away from the pole and are conscious of the offset of the mirror from the (main, non-mirror) truck body, but then I would say that introduces "feel". [Note, this assumes that you don't know the specific measurement of, say, your seated position to the location of the mirror, and could then estimate the amount to offset the truck, and drive so that the truck path is the correct measurement to strike the ball--Ironically, this could be done back on the pool table, where the equipment measurements are known!]
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