I know you have and I've read your posts over the years, but I've been gone a while and so I guess I had a bit of built up energy. I read your methodology as rude, but I'm sure you had no intention of being rude, so I apologize.
Apology accepted.
As to the post, I was curious mainly, whether this technique was understood or was being employed to any degree. After reading the myriad posts regarding gapping and the wide disparity in results, I wondered how many if any, were aware of and utilizing secondary aiming. As I read the responses, here at least, I feel that it isn't well understood. What may possibly be hampering that understanding is in thinking it is the same as gap.
Let's refer back to Hill: "To anyone wishing to learn the split-vision or secondary-aiming method in shooting a bow, here are practical directions to follow:
Select any given object to represent the target to be hit, and focus your eye on that object. Using the right hand, closed except for the index finger, bring that finger into your field of vision. At first it will be difficult to keep from shifting your direct vision away from the original or primary object, but after some practice it will be easy to hold fast with your direct vision on the original object, looking at it primarily, while secondarily you will be able to point your finger at any other object inside the scope of your vision, without looking directly at either the finger or whatever secondary object you have selected. Keep both eyes open at all times. As soon as the eyes have become accustomed to seeing in this manner, you are ready to begin using the split-vision method of aiming an arrow. You merely have to substitute your arrow for your index finger, using only the tip end of the arrow when it is at full draw to aim with."
If you get his instruction, you will see that it is not the same as calculating a gap in inches at various distances.
It takes some practice, but after awhile it will become automatic, furthermore, it works...