That is pretty funny.
Of course, he can only assume that the F U is why he was banned. I bet they didn't tell him that was the reason, only agreed it was likely. It could have been for poor conduct over the microphone. That for me is the main issue. THey should tell you what the violation was, or at least categorize it. Maybe three categories,
1. Conduct : things you say or do
2. Content : your profile or public messages
3. Cheating : mods etc...