In my limited knowledge of sports, I think that "follow-through" would include all the actions that follow the release of the ball. I'm told that follow-through is important in certain situations: after the release of the bowling ball as it begins its journey down the lane; the upswing of a pianist's hands when finishing a phrase. I'm not sure it's really important, but it certainly makes the action seem more graceful in most cases.
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Mr Wordy However, the sentence as a whole is worded as if the calculations "follow through" before the ball is thrown.
NewguestYes, it's before not after.Yes, I believe that this is the sort of meaning the author had in mind. I still don't understand how the calculations can prove to be right
I take it to mean that if all calculations done by the given person will prove to be right (follow through) he/she will know how/where etc. the ball will fly before it is thrown.