So, the swept volume RATE(piston speed) stays the same (because RPM stays the same) and we have double the density in the port compared to a no boost situation. If those two things are constants between our boosted and non boosted examples, then you would end up with an engine capable of doubling the horsepower by doubling the density without any increase in port speed. We can get pretty close to that in the real world.
Now take those constants, and add speed. I don't know how but let's throw that in there. Now you have twice as many molecules, moving faster than my previous example(pic any rate faster that you want but explain please) Then wouldn't any increased port velocity make the engine breath more and more efficiently as density rises. So 100% more air would make more than 100% more horsepower???? Sort of a perpetual motion type thing? I don't buy it, but I'm willing to keep an open mind. So far I'm not convinced.