nope, at idle the intake pipe has very little suction, if you put a gauge on it you probably wouldnt get any vacuum, whereas the plenum has heaps due to the throttle body being shut. obviously the closer you get to 0 vacuum in the plenum the less it would draw through from the intake side, until the pcv shuts as soon as you hit boost then it starts flowing the other way if theres any blowby.
@hanaldo, he doesnt think theres any unmetered air coming in, someone else implied that and has confused you