Instructing/coaching, I rarely get to teach anyone how to aim anymore. Believe me, I know how to teach them, and will occasionally use e.g. "Ghost Ball" when it serves an explanation (in particular showing something more elaborate than how to shoot an object ball into a pocket). But there are fewer and fewer new/young players, pool in this country at least is suffering from overageing.
As a result, I'm almost exclusively confronted with more or less experienced (some championship calibre) students. Players, in short, who know where to hit the ball, but occasionally don't.
Players like myself then. Ever noticed that the more experienced one gets, the more rarely one misses by more than a margin that no longer goes beyond e.g. the difference CIT (= collision-induced throw), let alone a bad contact (AmE "skid", BrE "kick") dirty/sticky makes? In other words, we're talking tiny little differences that, quite honestly, at my age, become increasingly hard to see (tell), let alone compensate for. Seems like in the long run (= even more so now than when I was young and eagle-eyed), it all becomes a matter of feel.
What I always knew to be the superior "system". There's no real substitute for the feel developed through practice (although admittedly, it'll come more easily to some of us than others).
My experience teaching people, by the way, is that most people miss because they didn't hit (the cue ball primarily, the object ball secondarily) where they intended to, and not because they aim off target. It's a matter of being honest with oneself: it's not about counting how often one misses, but how often one couldn't pull the trigger because there was no way of making sure that the intended aimed-at spot is indeed the right one. In the final analysis, those are the only shots that call for a "system". All others merely call for making a decision, stick to it, and execute.
And maybe (perhaps always): try and get a feel for it…
My two cents worth…
Greetings from Switzerland, David.
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„J'ai gâché vingt ans de mes plus belles années au billard. Si c'était à refaire, je recommencerais.“ – Roger Conti
I like your post David. You made your point quite well with civility and clarity. I don't agree completely with it but I appreciate your insight from your perspective.
I do agree that most shots are missed because one doesn't hit the cue ball where they intended, as they intended or that they didn't hit the object ball as they intended, where they intended.

I've seen many students who for whatever reason have trouble "seeing" certain shots correctly. I believe that the aiming systems of today have become excellent teaching tools that far surpass what the ghost ball principle illustrates or teaches. The ghost ball is quite simple and geometrically perfect but you can't see it and can only imagine it.
Most of the newer aiming systems incorporate a wider range of fundamentals that include complete body alignment, body movements and especially eye positions that enable the player to get into a better position to have a chance to make the ball, if they hit the cue ball correctly and if they hit the object ball correctly. The newer aiming systems seem to focus on finite portions of the object ball and the cue ball and this seems to help some players to "see" the shot better.
I'm just curious though:
What is "overaging"?
Thanks!