Here's my take on it for what it's worth . . . .
Unless you have the scoop placed in an air flow that would in fact have the thing take advantage of the air velocity (as that's what drives the air in) such as a top fuel dragster with the scoop up high, then you're not really getting a ram effect (compression).
What we can do is take advantage of
high pressure air zones. That being in front of the radiator area, and the base of the windshield.
We've all had the experience of passing a big-rig at highway speeds where we get blown to the side as we pass the front of the rig. That's all the air that the rig has to push to the side and over the vehicle as it moves down the road. You could almost view it as a bubble of compressed air.
Perhaps you've noticed that on really humid days, as you come up side of the front of the rig, water drops mysteriously get blown around on your windshield. It's broad daylight out with no rain! . . ? The rig pushing through the air, compresses it enough that some of the humidity condenses into a liquid (water).
While our trucks don't move that much air, the effect is still the same.
The taking advantage of such is nothing new. Consider the '70's muscle cars that have the hoods that allow the intake at the base of the windshield.
With that, it really doesn't matter how you grab the air be it a scoop under the front bumper, or behind the headlights, or the base of the windshield.
In those settings, you're gonna flow much more air as compared to the typical hood scoop simply because it's subtly compressed (at highway speeds).