I'm moored near a winding hole and a long boat came to turn. I could see he was doing a beautiful job and could fit ok but out of courtesy I put my head out to ask if he wanted me to pull my boat back at all. No, he was fine. It was such a smooth turning (unlike my usual 24 point turns) that I asked if he had a bow-thruster. I suppose I thought that if he didn't, he might feel complimented on his boat-handling skills. Oh no! He said with real vitriol "No, why would anyone want one of those bloody noncy, noddy toys!". I just nodded and went back inside, insulted on several levels, even though I don't have a bow-thruster myself.
A moment later, he was backing past my boat towards the water-point and sure-enough, his bow hit my stern. I've never been happier to be hit ;-)