bgram,
I was shooting a tab with my heavy bows and kept curling the arrow off the shelf, very frustrated ! Switched back to a glove and took advice from Terry Green and starting shooting much better. My problem with the heavy bows and tab was that I was NOT able to start my draw with my fingers pointed backwards. As soon as I got a thin glove I was able to point my fingers back and can now shoot upside down reverse cant WITHTOUT dropping the arrow off the shelf !!! Make sure you get your fingers pointed back instead of perpendicular. If you are shooting a heavy bow, >60lbs, as you tire you will tend to tense your draw hand and curl the fingers and back of your hand during the draw and flip the arrow off the shelf, IF you started with your fingers perpendicular. Hope this helps someone as much as it helped me. I was about to pull my hair out before Terry turned the light bulb on for me !
nocams