It's funny. I was going to write a piece very much like the RDS one myself.
Clearly, I wouldn't have to go "undercover" as I can just be a regular fan and still manage.
Anyone who has been to a Habs game when Boston is in town will be familiar with the banter that goes on. It is for the most part harmless, as most Bostonians choose to resort to irrelevant arguments like baseball and football when the hockey goes sour. Most outspoken Boston fans, despite their need to have the last word, adhere to the rules of sports banter: keep it to sport.
It's always disappointing to hear that some people resort to personal attacks, such as the one in the RDS post. I like to believe it comes from a minority – hence the reason I chose not to post on it myself (until now, anyway).
I was thinking just yesterday, however, how tame the response of home fans is to armies of (often obnoxious and inebriated) away fans is in North America. Having attended several football matches in the UK and Italy, I can tell you this RDS reporter got it lightly. Several times I have had to pretend to cheer for the other team and keep my emotions in check when finding the scalper's last tickets were in the away section. In Italy, I thought it best just to enjoy the game for the game and not really support anyone. How ridiculous is that? I suppose, it's something we can be thankful for and be proud of in North America – that supporting a sports team does not often spill into matters of survival.
As for Boston fans, I bet if you caught the same Bruins fan on a different day, he would be deep into an explanation about how his team with Patrice Bergeron would be sticking it to the Habs. What's more he'd be doing it in a sweater numbered 77...