Ok, if you dont believe it lubes the upper cylinders how about this: it is energy that is burned, and you are wasting it. Also, the small vac from the intake sucks out positive pressure. Vac pumps on ccv systems are PROVEN to increase power and efficiency.
So the exhaust valves don't need lube but the intakes do?
The upper cylinder thing makes perfect sense.
exhaust valves wear at over twice the rate of intake valves, i would say a lot of that is due to heat. the main reason for routing the crank vent to the intake manifold is emmissions, some nasty *** comes out the ccv, i don't doubt that it also contributes to lubing valve, but i'm thinking it also contributes to carbon build up on valves and run aways.