Here are some of the reasons people struggle with aiming.
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They assume they have a aiming problem when the main reason for most of the misses are do to stroking.(Or vise versa.)
I think people who really have an issue with pocketing balls is that they havnt trained them self's that you cannot address the
same angle the same way when the shape for the next ball requires you to do something different on the cb.Its like where trusting are eyes and stroke when the whole reason for the miss is lack of practice for that type of hit on the cb.Here we have an issue ,we blame aiming and stroking on are misses when in truth we dont no how to correctly address the shot. Take that one angle and pocket that ball with all the hits required that you must learn on the cb.Then your pocketing becomes stronger,you feel better when your at the table.Hey i no how to put myself in the best possible position to make this shot.To me there nothing worse then shooting a shot scared because your unsure of how to hit it.
Just practice every type of hit from one angle different speeds different distances,then change your angle .Practice this and then you get a better feeling on how to approach the correct line for the shot.
I still miss but i dont shoot scared anymore.