Being functional and being effective are indeed two very different things.
Though, effectiveness is something which could be argued about just any factory scoop even if functional. I mean, just how effective is the functional shaker scoop on the 03/04 Mach 1's? Its opening is right at one of the worse possible places for attempting to suck up air (the dead center of the hood is a very low pressure area).
A functional and effective hood scoop needs to be either (1) at the front most edge like the concept Mustang and late model Firebirds, (2) at windshield edge facing rearward like some Cobras, or (3) raised up high like on dragsters.