There is conscious gap aiming and unconscious gap aiming. One the latter is learned it can be reflexive and yes, muscle memory allows for some adaptation.
Veey easy to corrupt ones form and followthrough as the day progresses, and still hit good.
Next day however, starting out fresh body but corrupted sight picture from day before, its pretty horrible.
The smaller the gap from arrow/ bow hand to target the faster and more accurately the brain learns the sight picture.
3 under or if going split, middle finger corner of the mouth helps.
