Many sources state that squeezing the finger spacer allows for less nock pinching when shooting split finger. Recently on a Push podcast it was mentioned by Tom Clum that it also allows for a better hook and the keeping of the hook shape upon release. In other words it promotes having the string "cut through" the fingers rather than you opening the fingers and influencing the release. I shoot Rick's split finger tab but shoot 3 under with it. Pinching does do what Mr. Clum states; in my experience. So the question is, why don't you put a spacer on a 3 under tab?