(Verb)
If one ‘Counter-Banters’, it is the action of deciding not to take part in some casual banter that a mate is having with you; it is to kill an exchange of banter stone-dead.
“Ah that’s a shame, I was only being sarcastic and trying to have a laugh, instead you decided to take the matter seriously and shut me down. That was a real case of counter-bantering.”
The Bell Curve of Banter is a scale used to determine whither a joke or action is funny or "too far". One would compare the action which has just occurred with a typical bell curve with the very apex of the curve being top notch banter where everyone is having a great time. If any parties involved are adversely affected to the point where they are no longer enjoying themselves then the current exchange has surpassed the Bell Curve of Banter.
John: "Did you see that?! I just ruined Mike's chances with that girl!"
Gary:"Nah man. That's too far. You've surpassed the bell curve of banter."