K,
I think what you are referring to is using a mark on your riser face (the part you see) to set elevation for the distance to be shot. What you might try, is to place a piece of tape horizontally on your riser. You will have to experiment to find the correct height to place it. Let's say you find a spot that the bottom of the tape puts you on target at 20 yards, Then you can find out where the top of the tape puts the arrow. I've seen some shooters with two "tapes" on their bow for 4 different distances.
This is very close to using a sight, the difference is that you still have to get the windage right. This really isn't a "point on" system as you will perceive the arrow below the target for closer distances. Absolutely nothing wrong with doing what works for you!
For what it is worth, I don't believe that "subconscious aiming" is causing your snap shooting. I believe that your subconscious is short circuiting your shot process while your conscious mind is aiming. You might try this experiment. Consciously think through the shot from draw to anchor to follow through while ONLY looking at the target and pointing at it with your bow hand. Don't think about the looking or pointing, just do it. See if that might work for you.