Now, if throttle loss reduction was the goal, I can think of a couple of ways to do it.
The first would be to slap on a smaller bore throttle body with a nozzle at both ends. As that simple metal disk deliberately causes aerodynamic drag in order to throttle the air, it would make sense to decrease the size of that metal disk. There'd still be a restriction there, but it'd be smaller. As the air is sucked through the smaller bore, it would get sped up, and in the process its static pressure would drop. Once the sped-up air got past the throttle plate, it would be expanded by the nozzle, which would slow it back down to feed the engine.
The other idea would be an extension of the first one above: A variable venturi. Here, no throttle plate is used at all. Instead, the properties of air are used to perform the throttling.
This guy had a pretty good idea:
PRV Performance
Keep in mind that the intake vacuum would still be there, but at least throttling losses would be much reduced.