Why does Edelbrock cut some plenum dividers and not others?

Hey All:

Been thinking of cutting the plenum divider in my air gap to see if i can squeeze some extra out of it.

Looking over the manifolds on Edelbrock's page, I noticed that the Chevy Air Gap is cut pretty serious straight from Edelbrock, and that the Ford 302 air gap is cut, but to a lesser degree (Ford 351W is not cut at all, same as Mopar).

Anyone have a clue why they might do it that way?

Anyone ever cut on their air gap?

Steve