I' m by far no expert, but when I tried out my first savage it proved accurate at the variable heights and distances I shot it at. From 15' up to 23' up from 5 yards to 30 yards. And that was with a slow 235 fps arrow.

I have the newer savage pendulum supermax and will tell you IMHO, your not missing anything with your older design. The round sight housing is too small to actually make the circle fit the outside of my peeps circle. The wing nuts will not get it tight enough to hold true without further tightening down with an Allen wrench (my horizontal kept moving on me).
I did spring for the tritium pin and was shooting by moonlight the othernight. Really impressive groups to boot. Although I know of no game animal wearing all white with a round circle in it' s kill zone (like my targets face).
I need to try it out before season to see if all is well from varied distances. If so, I' m gonna leave the mathmatical questions to someone else and just hunt. If it works, it works!!