As I alluded to in Violence Part I, I'm kind of incredulous that the video linked to in "[uOttawa Community] President Rock, Please Stop" is anything approaching the "The True Face of Allan Rock". In fact, it seems to me that there was obviously some serious backstory that had been elided by the authors.
Since the backstory was not forthcoming, I have helpfully filled in my own version (which is likely to be far more interesting than what actually happened) and summerized it in a helpful little cartoon:
You vs. Me vs. Genghis Khan
I'm not trying to blame Mark Kelly for being so annoying the President of the University lost his cool (after all who wouldn't want a basket of cockroaches?), but rather trying to point out that a single interaction hardly defines a person. As hard as it may be to believe, raising your voice to a single person, in a single instance, does not make you a violent sociopath regardless of how many views the YouTube video gets.
A few years ago I surprised myself with the realization that people are capable of an entire range of behaviours and interaction modes. For your convenience, I have drafted a (completely unscientific and inaccurate) handy model of human behaviour charachterizing both a normal person (blue) and violent sociopath extrodinaire Genghis Khan (red).
You'll notice that while both the normal person (in this case Mr. Rock) and Genghis Khan are capable of taunting and yelling, the frequency with which each resorts to a given interaction mode varies greatly. While Mr. Rock may have yelled at Mark Kelly, I doubt that the last hundred people who passed through the threshold to the President's office recieved the same treatement. Honestly they couldn't have, otherwise, Mr. Rock would never have got, nor kept, any of the positions he has previously held.
"Get out of my office!" is not the real Alan Rock. "Hi, how can I help you?" is the real Alan Rock. "Get out of my office!" is an outlier. It's one sample. It doesn't really tell us anything about Mr. Rock other than, just like every other person, if you annoy him enough he will yell at you.