Found the book "shooting from within". Skimming a bit to help you made me realize I need to read the whole book again. What Plaxco has to say about vision, focus, and concentration is of benefit to anyone aiming at a target I believe, even if the target is a spot on a pool ball. The book is about competing with guns, primarily pistols, but a great deal transfers.
Eye exercises include selecting maybe a half-dozen objects in a room and practice focusing on each one sharply as soon as you see it. You can start with only two objects. What happens is that your eyes learn to change focus as you move between objects and you acquire the sharp view of the new object faster. You also seem to see clearer because you don't have the memory of the blurred view of an object.
Another exercise is to find or buy a cheap clock with a second hand. Focus on the tip of the second hand for as long as you can, rest, and do it again. This is actually a fairly brutal test as I recall. Far harder to really focus on the end of the second hand for a minute than I would have believed.
Another test is to focus intently on an object across the room. Without taking your focus off of that object, try to identify objects in the far edges of your vision and see them more clearly.
Practice focusing on the exact spot you want to hit the cue ball and the object ball. Refine that point smaller and smaller.
Even in the few minutes I read to gather this information I read other things of interest. Plaxco believes that mental focus and visual focus are tied together. Increase one and you will increase the other. He also has a section on turning concentration on and off. This is important as I have found that being able to turn off while I am sitting in my chair waiting for the other player to finish his inning is much less tiring and lets me focus intensely at the table for much longer periods of time.
Thanks for the thread, reminds me to do some rereading of old books!
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