I've fortuntaly not had anyone in person quite as bad as what I've seen here on the forums, and what you guys have described, but I've had a few "know it all" types.

When it's a kid, I usually take it as a form for entusiasm, the desire to know as much as possible and do as much as possible as quickly as possible. So, if I'm asked for help, and I get the "so-and-so does it this way" or that kind of thing, then my answer is "yes, well, there are many ways to do things, do you want to try it that way?" then I step back. I also don't mind letting someone try something "their way", unless I really think it might endanger others. Even if I think the answer isn't the best way to do things.

The adults, I'm less tolerant of. Usually, if I start getting grief from one of them, it suddenly becomes time for me to fly my plane, and it's amazing how bad my hearing is when my engine is running (I've yet to have someone I wanted to go away follow me to the pilot stand when I'm flying, but I suspect it's happened to others)

"The foolish man knows only what he knows. The wise man also knows what he does not know."