Have you noticed they "double snap" onto you string. It looks like there is a option when snapping your arrow on. The first notch seems just tight enough to be secure and is very near the end of the nock and the second is deep in the bottom of the nock and alot tighter.
Has anyone noticed any difference in the arrows placement on the string? I'd guess the first position would be less disturbing to arrow flight? Or is there some other significance to it that isn't obvious to me yet?