I shoot with both eyes open, even with the scope when it's on the rifle. I always see the orange ball depending at what position the sun is in.
When I worked with my Daughter I watched her close to see what she was doing before she broke the shot. I could see her changing her grip just before the shot broke. Sometimes I would see the shoulder move as the shot broke. This is the most unconscious movement she made. She would say when I asked if she tensed up before breaking the shot and usually the answer was I don't think so. Pushing the shoulder in is the most common unconscious issue shooters have, anticipating the recoil. This will change the grip and stiffening up the shoulder. I could see her grip change by the way her trigger finger tightened up against the wrist. I changed this by having her put het thumb against the side of the stock wrist so she cant grip the stock wrist to throw that shot as she breaks the shot.
I would ask her where did the shot break at and before she would answer I said did it break right? and her answer would be 2-o-clock.
Anticipating the recoil is an unconscious reaction the shooter most generally don't realize doing it but can see it if they break a shot with out having the hammer cocked.
Kurt