I have been bothered most of my life by pinching the arrow nock. I was envious at times of the spacer that was available on shooting tabs but never seen one on a shooting glove.
I made this finger ring out of scrap leather:
The pad is concaved just a little to index the index finger along the middle finger.
I dont know if I am the first to ever try anything like this but it really helped me out. No more callous on the edge of my finger and nail too.