That guy cobraracer46 makes no sense what so ever. You are constantly pushing or pulling air through the motor. Even with the stock setup in place this happens. His story has no merit what so ever.

The PCV setup is a pollution control device plain and simple.

I ran those breathers on my car for a long time with no engine damage or premature breakdown of the oil. Obviously the best setup is using a pump that will create a strong vaccum but thats expensive. The next best thing is insuring you have equal pressure inside and outside the engine ie: no positive crank case perssure. Breathers will accomplish this. The PCV setup can be a restriction especially at WOT were manifold pressure in near 0.