I remember being on the line for a contrib game where one player was on the ref's back constantly, telling him he was a sh!t referee. He gave a free kick on the edge of the area, said player took it and put it into orbit. The referee ran past him and said, rather too loudly, who's sh!t now then. Everyone was laughing, he was well and truly put back into his box, and he didn't get a peep from him for the rest of the game. The benches behind me were in hysterics. Unprofessional? Probably yes. Effective? Absolutely.