It is a proven concept in the intake runners or the ports themselves. Most manufacturers just go for opening one intake valve sooner and more than the other to accomplish in-cylinder swirl tho.
And Thus why the VX would see no improvement from a vortex generator anywhere before or after the throttle body....the ECU only opens three valves to create a swirl effect in the combustion chamber before VTEC engages. It only opens the fourth valve enough to clear any fuel on the backside of it. but once VTEC engages all four valves are opened (when needed) and the combustion chamber is changed to a tumble type combustion process.