I never appointed myself the arbiter of anything. That said, being a member of the community to which your original post was directed - and the only member of the CC community commenting - I am compelled to give my opinion.
As for it being dangerous for a group to define civility, I would point out that the very definition of civility is the adherence to generally accepted standards of behavior within a community. Again, I am the only member of the community speaking in this thread, thus the only one able to convey a general, non-scientific consensus of the community. I do not purport to know anything about the discipline process. I have my own opinion as to whether the resultant suspension was justified or not. That said, I must agree with you that if the real world holds for me an environment where any individual can capriciously define civility and act in a boorish manner without impunity then it will be the society that is rude, not my awakening.