But some will agree & not understand that if one is constantly thinking about little stroke details during 'practice' it is very difficult to turn that off when actually playing.
I don't agree with this at all being a problem. Will it happen in the beginning yes, but give it time. Some people I have been working with have made comments about thinking about all these things has ruined their game, as it did with me. This is 100% true.... for a little while. The example I give them is that it is like learning to drive a stick shift. At first you have all this information you are thinking of and trying to execute so you shift bad, can't shift during turns, kill it at lights, etc but over time it just becomes second nature and you do all those things without a problem. Why is that? Because the fundamentals of shifting have been solidified enough over time that you just naturally do it. The exact same will happen with your pool game regardless of that it is you are trying to learn.