I will admit to not knowing the guy who invented it, or anything at all beyond the general principle of the thing. But I can't sleep at night now from not knowing. With full respect to other theories, and ketchup, I would like to have a stab at it myself.
If it is indeed a hollow chamber, and they have gone to the trouble of making the thing at all and not just directly venting the blow-by through a tube, the purpose of the different size holes might be to make a little vortex inside that chamber.
To my thinking, it could either be to ensure nothing solid makes it through that last trap. Or, more likely, given conventional valves, to regulate the flow. Increased vacuum would cause increased resistance, because the vortex would swirl faster, right? I mean, if it was sucking too hard, then **** would get sucked up there for sure.
Anyway, I have so fucked with it now with my drill, ha ha. Let's see how it likes that.
I am gonna put the catch cans on because I have bought them, and because they look like parts from the Death Star. Surely Darth Vader can make improvements.
It will allow me to satisfy my curiosity about whether much **** is coming through that valve, and whether the more expensive oils are that much worth it. Maybe too I have now caused more **** to be inhaled.