Great discussion. I'd like to expand it. Since it sounds like you guys have been doing this longer than I have, what's your take on BJJ or other grappling arts in a street fight situation with the potential of multiple opponents?
Well, I've heard this many times and honestly it's the main question posed about BJJ more often than not. I'll try to answer it as best I can.
I have been training in BJJ, Judo, wrestling, etc. for a while and I teach BJJ. When someone comes to me and asks "what's the best thing I can do when being attacked my multiple attackers?" I tell them the same thing "talk your way out of the situation or run". I've also trained in Muay-Thai kickboxing for over 7 years and I would give the same advice to someone who asked in regards to Muay-Thai.
The bottom line is when there are multiple attackers all bets are off. They don't want a fair fight so the best thing you can do is get the hell out of there because they'll likely do anything they can to win.
Now if you have no choice whatsoever and you are forced to fight multiple guys I would not personally bring the fight to the ground. I would try and keep it standing and look for a quick "out". Given the situation if the fight was forced to the ground I would try to end the first guys fight quickly with a very quick and devestating sub that would break an arm or leg, which might help to discourage the other guy...at the very least it would give you time to get back to your feet. I would only look for top position, which would give me an easy way to get back up. If I got stuck holding guard I would try to use the guy in my guard as a shield as best I could against the strikes of the other guy...if you have a descent guard it's not hard to move someone's body and use it as a shield.
There are things you can do and you can make BJJ effective on the streets without doubt. When you start talking about multiple attackers no matter what style of martial art you do there isn't much guarantee.
One thing that I can add that is great about BJJ is that if you don't want to fight on the ground like in this given situation, you won't find many guys that are better at getting up than grapplers. Most grapplers spend so much time on the mat that they get really good at getting back to their feet...especially wrestlers and Judo guys.