ORIGINAL: Rob/PA Bowyer
Nope, I understood, you didn't

, that's why I gave the paper as an example, they wouldn't open on paper if they were stopping the arrow...comprendo mi amigo? Hell I don't know either, that's why I brought up for discussion. Has to be coincidence.
I think what he meant is AFTER they move to open which you have expressed they do with little effort (paper) what happens to the little tabs? is there still some portion exposed on the leading edge of the broadhead? If so then they will slow the penetration because even though they move easy, once fully open and at their stopping point they wont move anymore. Unless those "tabs" dissapear completely they will slow the penetration.