We had one in our house today... a plumber I mean. I was being all enthusiastic, taking an interest in what we should or shouldn't do to our toilet in order to get it to stop slowly leaking all over the bathroom floor and seeping through the kitchen ceiling, being a responsible citizen and all. And maybe it was the way I said the word "Ball-cock" that made him take offence, especially from a lady of my current stature and medical condition... but he actually couldn't physically hear a word that I said, and consequently didn't answer any of the many intelligent and probing plumbing related questions that I fired in his direction.
Luckily the deafness extended to my maniacal laughter when comment after question met the same non response... I've left Mr VC to "sort him out" - and by that I mean pay him loads of money for coming to our house and treating us like something he stood in, it's a much sought after service in some circles you know.