I would use two whether I shot split fingers or three under. The arrow will move up and down that string upon release. Only takes 30 seconds to tie on a lower nocking point.

Two. I think it's cheap insurance. (watch the video). I can't imagine why it would make any difference whether you are shooting split or three-under.

Two

 2

Two

I shoot split BUT I still find 2      One over and one under, to give me the best      & most consistent arrow       flight (tie on )

2 for sure. There's video floating around, slow mo, showing arrows slipping down when knocking only above the arrow. This is true for split as well

Two  

I like two. God bless.

I just switched to 3 under and found a world of difference in shooting. After watching the video, I will also be tieing on a lower knot. Thank you for the tips.

I changed to two under and haven't shot better!