There's a few engine builders in this thread lurking
There's a lot involved in terms of air flow. This engine is simply a pump, just like ANY internal combustion engine. Only difference being the ignition. It's still a 4 stroke pump.
We are always under a boost condition, even without a turbo. Atmospheric conditions produce boost as well, but it's just a small amount. When a cylinder is past TDC and the intake valve is open, it is not 'sucking' air in... the void created is allowing atmospheric pressure(boost) to fill the cylinder.
As for cylinder heads and air flow, regardless of the amount of boost, whether atmospheric or mechanical, there are conditions that exist in the ports, whether it be intake tubes, manifold, or cylinder head, that simply put, 'mess' around with the motion of air flow.
Much revolves around Turbulence. In a dry manifold condition as we have here, we do not want a turbulent condition. We want a steady column of airflow. Not a mixed bag of low and high pressures.
Obviously one look at the entire system tells us we're living in a dream world if we think we can even 'minimize' the turbulence with a bolt on that exists prior to the turbulent area. What happens in MAIN intake manifold AFTER the Banks manifold? The air column hits a giant wall in the floor.
Aside from turbulence, what in the system is the choke? I'm not convinced that the pre-intake manifold is the choke.
Oh well... just some thoughts.