You should put one speck of dust somewhere on your engine and post a photo offering a prize to the first one to find it.
I truly can't recall ever seeing an engine so clean. Even more impressive is the workmanship. To me it's these details that lend credibility to our choice of recreation. OK, that being said,
I was under the impression that the "P" in PCV meant positive displacement, or air going out. But where I get confused is why one side will have the one-way action of a "valve", the other side is merely vented to atmospheric equality.
My only point of reference on this is building Harley-Davidson pan and shovel head engines. They have a breather gear that is actually a hollow tube with a window cut in it that is timed with the crank position to open and release pressure at the right interval in the cycle.
However, there is an additional vent out the back of the crankcase housing that is typically left open, and only pcv'd as a "performance mod" by an obscure few.
See what I mean?
Why pcv, only to vent too? Buuuut, that seems to be extremely common, and also works well. Why?