I'd never let things get as bad here as the story you described.

Generally, I try to use others' characters only after someone else has on the board, and I try to be careful - the question in my mind being will this character be useable in their own context after the story is done? It wouldn't be prudent for example to have Visionary lose it and start carrying around an assault rifle, for instance.

Sometimes what trips me up on that is if that character has only been used by another writer with very specific criteria, or if only that second writer was given permission just for that one story. Like if you're told you can only use the brand-new Exploding Man for one specific arc, and I see him in there, and try to use him also and then tempers flare because of it.

I also try not to use a character in too much of a mocking manner, unless it's true to context (like Visionary or Al B Harper). Of course that can get messed up too, like if I write something with Visionary getting himself in trouble as usual, and then the poster tells me he's sick of that and he's trying to give Vizh a better image.

Even then, though, I still find myself often running into situations where I cause people to get the impression that I'm mocking or misusing a character when I'm not. And that's simply because I try to use different and more unusual or complicated situations than normal. Maybe ones those characters shouldn't be placed in, I dunno. All I can do is try and see how it turns out.