I don't want to get pulled into an aiming system argument, but I will address the ops question.
Gaining ability in pool is more about obtaining knowledge than anything. The knowledge that goes into top flight pool is so vast, it is difficult for most to grasp.
There is no such thing as a total feel player. Players who rely on instinct typically have tons of knowledge that they are applying along with gobs of practice and usually relatively sound fundamentals which goes back to knowledge again.
There are basically two types of knowledge that apply to pool. There is game specific knowledge and there is personal knowledge.
Game specific knowledge is best illustrated by top one pocket players. They usually had someone coach and show them this knowledge. It is very rare for people to attain game specific knowledge on their own. They are usually taken under the wing of someone at a young age because they show promise or a strong desire.
While this type of knowledge is necessary to attain high levels of play the knowledge that usually leads to the most improvement is personal knowledge.
Personal knowledge is knowledge about your game. What stance works best for you, what bridge, what preshot routine.
Personal knowledge is knowing what you do wrong when miss and what you do right when you do what you want.
There is a danger in using HAMB or other "Instinctual" learning systems. This is positive reward for negative behavior.
If both your aim and your stroke is flawed, you will make balls and reinforce those flaws in your game.
This is the biggest reason why people usually have to start at a young age with a good mentor.
Once those negative behaviors are positively reinforced, it becomes VERY difficult to get rid of those behaviors and people will often wonder why they miss even when they feel they stroked it right, or "Knew" they were aiming right.
This is where aiming systems can help. If you have an aiming system that you KNOW is accurate, it can help to isolate flaws in your stroke.
Here is the downfall in this though. There are TONS of variables that any aiming system has to account for.
There's squirt, CIT, swerve, etc...
However, once you have a starting point AND you practice a LOT, you can better learn how to adjust for these factors and develop the personal knowledge to know what best works for you.
There's a reason that stagnation occurs and gains in ability seem to occur in huge jumps followed by periods of lackluster play or even reversions to lesser ability of play.
It's because you are having to learn all of these minute changes and then adjust your style of play to fit your new personal knowledge.
This is one reason why there are specific progressions people should follow if they want to maximize their ultimate ability.
1) you shouldn't be hitting balls until you can readily repeat a good stroke with a solid follow through.
2) When you do start hitting balls, you should be using a simple, easy to use aiming system like ghost ball that is not too convoluted.
3) You shouldn't be trying any English without first understanding what is involved in it. I.e., understanding tangent line, stun, parabolic curves for follow and draw, CIT for certain angles and conditions, squirt, swerve for sidespin. These are some of the prerequisites for advanced position play.
4) advanced understanding only comes with knowledge and experience using that knowledge.
I can't reiterate enough how much knowledge plays a part in advancing your ability. The biggest reason for stagnation is a lack of attaining greater knowledge in pool.
There is a tendency when gaining greater ability, to think you know it all and that all you have to do now is practice. You never have too much knowledge and you rarely if ever have enough, depending on what your ultimate goal in pool is.
Jaden