I usually don't get involved in these types of threads, but feel the need to point something out, maybe it will make a difference, maybe not...
First, interesting info about the gun sights. I will be taking a concealed weapon's class soon with my wife, neither of us have ever shot a gun. I'm thinking will be good to learn, and even cool to learn how to aim properly - like how you've pictured - and practice good technique to enjoy going to the range to practice.
In your example - using SEE as I do, or 90/90 I believe is similar - I would be aiming the outside (left) edge of the CB at the inside (right) edge of the object ball. Those are two pretty objective points, especially at that distance, vs. trying to aim at a point that is 1 1/4" away from the object ball and at a slight angle toward the shooter. Then I simply step into the shot a certain way and go to center CB, a repetitive movement learned from practice.
I don't even look up at the OB for any real reason after my initial alignment - no reason to, I don't feel I can accurately judge the hit at that distance anyway. A matter of fact, usually when I "fidget" on those types of long tough shots and try to make small corrections I do more harm than good. My initial alignment is almost always perfect based on my alignment of the CB to OB and the movement to CB. The main issue here is not only aiming properly but then stroking straight as well. I can make even tougher shots with the OB in the middle of the end rail - same alignment, same movements.
There is a shot in the Billiard University test, drill #1, a progressive cut with the OB in your position, 1 ball off the rail, 1 diamond from the pocket. CB at the hardest level is 1 diamond from the opposite end rail and 1 diamond from the right long rail - so off the rail a little more than yours, but technically even a more acute angle. I made 10 out of 10 for the drill several times out of 5 or 6 attempts, and would expect to make 8 or 9 out of 10 frequently.
Now this is a very tough shot, small margin for error in aiming, stroke deviation, etc. Could Thorsten or Archer or whoever make just as many or more with whatever method they use? Sure, for many reasons. But for me, with my poor eyesight at that distance due to astigmatism, I am WAY better and more confident at those shots since using SEE or Pro1 than before just guessing. There is zero anxiety when shooting that shot, since I'm just aligning 2 objective points and getting down on the ball the same way I would for a 12" straight in shot. Those repetitive movements, standard PSR, etc. make shooting difficult shots no more difficult than any other, you are shooting the same 2 or 3 shots over and over. When I practice shots in certain categories, or do demonstrations or clinic, I specifically do NOT use donuts or mark the table. I shoot difficult shots from random locations - same family of angles, but a little more left, more right, more or less distance, etc. Just to show that the alignment and movement works regardless of the exact position.
Regarding the objective vs. subjective - If you were asking me to aim at 9/16" of a ball, then yes, that's really no different then estimating a GB center. But when aiming using edges, or the center (which is sort of subjective but very easy to estimate), or the shadow under the ball (which is in a VERY consistent location shot to shot), we can feel like we are using objective points to aim with, and that every shot is the same. It promotes a similar feeling and process from shot to shot, which has a direct affect on one's confidence.
I'll leave it to debate as the wars wage on whether these are "systems", "methods", "tricks", etc. I may be a little more open minded than most, I don't even know how they work and I use them, and I've had questions that have not been sufficiently answered as well and/or met with resistance. But unlike other keyboard warriors, I took it to the table, studied the material, asked questions, and gave it a chance. If you do all that, and you still don't get it, then great, they may not be for you. My pool partner, a top player in the area, is very visual, and thinks what I do is crazy - lines, shadows, etc. Yet recently he asked me to show him, since he's seen that much of an improvement in my pocketing confidence and doesn't want to miss out. I confused the hell out of him, it wasn't for him, but he can't deny what he's seen in my personal game.
Do I think everyone should learn an aiming system, or can't play without one? No. I don't even teach them in my lessons unless someone asks or I see someone grossly missing shots - usually there are far worse issues to resolve first. I just know for me, and others, they work and can be a great addition to one's game.
Interestingly, after conversations with a few pro friends of mine, I've actually reached a point where I don't consciously use a system on my more routine shots. I find that after a year or two of using the systems routinely, my sense of alignment and visualization - what "looks" right - has been enhanced so much that I can tell, system or not, that I'm lined up right. I don't consciously use or not use the system, although on tougher shots I 100% use it. But on easier to medium shots, I don't think about it and let it happen. I may be in the minority, but I've seen no decline in my ball pocketing, perhaps just a sloppy shot here and there. I did this after being told not to lose my "feel" and connection to the pocket by being too robotic with everything. I know that goes counter to most aiming system people, and my friends recommending this were not aiming system users, but I respected their opinion and think there's something to it. I think after a while, less and less conscious thought is needed to get down and come into the shot in a consistent and correct manner. I can still "see" the lines, angles, etc., I just don't need to stand behind the ball for 5 seconds to always consciously visualize them, if that makes sense. However, I always have something more specific to fall back on in pressure situations and on tougher cuts and longer shots.
Anyway, that's my rambling thoughts for the day. Maybe it will help you or someone else, maybe it won't. Maybe no one will read it...

Scott