I think the spin or "gearing" affects aim as well as the contact point. anytime you are hitting the OB so it is not straight on, and are also hitting the CB center ball you are throwing the object ball and you are causing it to spin..
I think I habitually compensate for that unless I'm using spin to direct the CB after first cushion.. someone else could go ahead explain it all better or in different terms. but I see that as a little "fly in the ointment" to think about.
Here's my take which may not be correct.. but Ill put it into my own words and the "experts" can agree or call me on it , this is just to see if I have it right , I'm not making a statement, I'm learning, and I'm trying to wrap my head around it..
a ball hits to steer the ball towards the left from the shooter's perspective, picture a 1/2 ball shot to the left pocket from the shooters perspective.
if the CB is running with no spin, the balls collide, the OB is then driven to turn CCW and so is the CB, by way of the collision the OB runs toward the pocket with spin.. the spot of impact is oppositte the pocket, The resulting spin of the OB isn't so important but it misdirects due to "throw"
If you can't see how the balls are spinning or ignore that and only see the trajectory, even though the ball is hit on the spot directly opposite to the pocket, it is undercut.. am i right undercut? or wouldthat there be overcut?
a better player will know this and compensate for the throw and also may choose to apply some left or right becaue when the CB hits the back rail it can be directed by way of it's spin and of course he's placing that CB for his next shot.
since he knows this he can apply more or less spin, but to maintain accuracy he needs to compensate for how much his spin throws the OB otherwise the spin produces inacuracy in itsef..
I think if I hit hit bal and was happy with the natural expected route of the CB and wasnt trying to change its trajectorry , then I'd hit the CB wiht some right, then the CB would already be running CCW slightly and this would then send the OB to the pocket rolling without any induced spin.. the CB would already have some CCW due to be hitting on the right, after impact it spins with about the same CCW rotation as the gearing ( theoretically ) matched up..
since the gearing was right there was little sliding action between the balls , as soon as the gearing is different here is some "skid" and throw induced.. That throw takes some practice to gain control over.
If my explanation lacked credibility, please don't insult me, instead try to correct what i said so it rings true in your own words..
for someone who understands the physics of double- clutching and why that reduces transmission fatige, the "gearing" , in pool, is essentially the same principle, Thats how I see it. If you did not understand the physics of doubleclutching then that would make no sense. some will and , some won't get that analogy.
now it gets a bit deeper because as soon as the player is hitting off center, he is also changing the direction of aim.. .. He is aiming for that contact spot opposite the pocket but hes taking itnto account that the spin affects his aim, so that is all happening as well..
to make it simpler to understand som will choose to hit the CB centerball and compensate for the throw of the OB by way of adjusting his aim. thats a different way to approach the same problem. in that case he's allowing the OB to spin due to the collsion and compensating for it in aim rather than using proper gearing..
which is right? maybe it's how you prefer? Im really not sure. It's a lot just to understand the physics.. I think there are lot of good players that understand the reactions better than the physics of why.. they simply practice until it works for them.. some others need to know "why it works that way" I'm in that camp. once I realize this works like this-- and the why, because of the physics of that, then the pieces glue together better, in my mind I know some who are very good players and if I said all that they would understand and perhaps agree, I know others who would look with eyes glazed over, and I'd know by that that I didnt get my point across properly.
I think I do something quite similar. There's no way I can describe everything, but about the cue on the shot line, I try to "feel" it as I'm getting into the shot. I may do a few strokes in the air while up to help get a feel. Once down, I'll do a couple feather strokes to confirm that I really did get down on the line. The feather strokes should not waver. You can do a slight adjustment while down, but unless it's absolutely minuscule, I'm much better off getting up and resetting.
