I'm not grasping your benefits from a less restrictive intake, unless you've got insufficient air at maximum boost levels.

If you're at 15 psi and you see black smoke............now you've got an argument for a less restrictive intake.

But, I'd make a wager that you're not at 15 psi with excessive fuel.........yet.

You're an engineer and you aren't "grasping" one of the fundamentals of fluid dynamics?

Any restriction on the turbo inlet produces a partial vacuum. The turbo can easily compensate for this, by increasing the pressure ratio and RPM. This can only be done by increasing the work done by the exhaust, which increases exhaust backpressure and increases engine pumping losses.

Just because you don't see black smoke doesn't mean your engine is running at maximum efficiency.

Agreed.

However, the question is the amount of the loss and the end result to the engine. If the intake causes a partial vacuum of........say........1" Hg........is it worth the effort to completely redesign the intake to eliminate it? The turbo compensates for the loss of air with slightly more boost and a bit of additional temperature as a result.

If you're looking for maximum performance, sure..........knock yourself out........but, you haven't done any intake modifications.........in favor of a different turbo with significant boost at lower rpm's. If it was that beneficial, you would have already done it.

Nobody is saying you'll get significant hp out of it, we are simply saying that there is a benefit.

When a person is looking to maximize efficiency or squeeze out every last 1/2hp, small details like filter ducting are noteworthy items to look at.