As I study what you shared, two considerations occur under one premise...
Premise:
While natural pivot lengths, BHE and FHE may keep the ball on your line of aim for off-center hits, spin-induced-throw (SIT) is still a factor
Thought 1: A firm hit may reduce swerve and also reduce SIT. Conversely a soft hit will increase swerve and SIT.
Thought 2: A thin hit doesn’t take much SIT vs. a full hit will take notably more throw.
I compensate aim for throw (SIT or CIT) during my center-ball alignment, before the pivot adjustment for squirt and swerve, per the info and demos in:
NV J.9 - "Got English?" – How to Aim Using Sidespin, With Game-Situation Examples
One more premise suggests a conclusion to me...
Premise 2: The table will challenge you with shots that require off-center hits as well as requiring various thin/thick hits at firm/slow speed.
Conclusion: Keeping the cueball on a line of aim with BHE/FHE/PivotLength is only one factor in a multifaceted shot. It isn’t the only thing to think about. In fact, it might be misleading to focus on it at all. It’s better to let your experience and feel dictate all considerations. Perhaps trusting automatic aiming if you’ve drilled/actioned (sic) properly is ideal. Especially if BHE/FHE is applied after settling down on the shot. My gut says any unnecessary movement after stepping into the shot (besides stroking) is ill-advised.
Thoughts?
Obviously, the best way to aim and align, taking everything into consideration, is to do so naturally (without having to think) as a result of countless hours of successful practice and experience. However, most pool players (me included) don't have perfect intuition for everything yet and can benefit from a methodical approach. But I do all of my thinking before a shot. I first adjust my aim for throw, if necessary, while "aiming while standing." I also observe the shot distance and think about the shot speed while I am standing. This tells me the BHE/FHE percentages that will be required (based on my
BHE/FHE calibration system). I have my calibration table memorized, so no thinking is required here (just rote recall). Now, without any more thinking or judgement required, I get down into my stance with a center-ball alignment (which is very easy to visualize), with my vision center over this line (before, during, and after getting down). Once down, and after I've verified my center-ball alignment and aim, I do the pre-decided BHE/FHE pivots (if the shot requires sidespin), take a practice stroke, and then and I shoot (all with no thinking whatsoever). The pivots do not bother or affect me one bit.
Before implementing this system in my game, I used to spend too much time trying to make small aim adjustments based on experience-based judgement while down on the shot (taking into consideration throw, squirt, and throw all at once). Now, I don't have to judge or think about anything. I just pivot and shoot.
Regards,
Dave