@dreamland: It might as well be heard... but thoroughly ignored
Some months ago we had a C182 IFR travelling through the area, taking half an hour crossing the paths of an unholy number of quite bigger in- and outs. Inconvenient to begin with, the pilot wasn't listening, it took an average of three calls to get a reaction.
He sounded like a nice chap though, until, after some "aircraft x, i say again, turn right h123 for separation", the reply was, "Sorry for not listening carefully, but don't you think I have something more important to do in here?" Quite baffled, half-wondering if the pilot was in trouble or something, my colleage said nothing.
Still, the good-bye was something like,
G: aircraft x, would you do me a favour?
A: of course, go ahead
G: Please, next time take the train. Would be healthier for both of us.