To put it bluntly - I don't tolerate it. Rule one of any of my Rp's is Gm is God and Gm has final say in all matters. I will explain once. If that doesn't do it, I will clarify once and place a ~this is the end of the conversation~ note. If it continues, they are removed and I have the mods delete any problem posts if needed. Keeps it short, simple, and to the point. Rather kick one quickly and keep things moving than have the problem spread through out the rp and risk killing it. 

Thankfully I have only had to kick one for such on this forum. I have had people leave an RP or ghost it after that ~shrugs~ But that happens in any RP. I have had issues before but my explain/clarify/done trifecta usually does it and we move on.