I think, to me - and like I said to Erika - it just strikes me as below Rodney to use insults such as idiot or moron as a form of banter when he's so much smarter than that. I can see Rodney using idiot or moron when angry, say, at his underlings. But to use it on John, to me, it doesn't really make sense to me when Rodney could use verbal prowess to further show off his intelligence. Using idiot or moron as banter would make him seem less intelligent, so I would think he would try to avoid them except when angry.

And I just... I really can't see John letting Rodney get away with it. John puts up with a lot from Rodney, but he also draws lines where Rodney's abrasiveness is concerned. There's a lot he doesn't get away with, because he knows Rodney needs some limits.

But, again, these are my personal views. I can't say for sure if they are tainted by my own real life experience or not. With some characters, I can totally see the insulting banter (I was watching the A-Team movie the other day and BA calling Murdock a fool and other such names didn't bother me one bit. It wouldn't be them without the insults). But with other characters, I often get the impression there are limits.