Respectfully, you are incorrect and assuming alot. I'm a ranked student under Rorion Gracie and you'd be surprised what someone like myself is capable of, especially against a sloppy untrained fighter like some bar bouncer.
Alot of BJJ guys like myself also train alot of stand up training as well, but the difference between us and most other martial artists is that we train all out everyday, full sparring. So we get a ton of real world experience in the process of our training. Don't label a BJJ practioner as solely a grounf fighter, I can just as easily choke you to sleep standing as I can on the ground.
As for his size, it means little in regards to a BJJ practioner. BJJ by design is made for a smaller opponent to defeat a larger one using leverage and patience. Helio Gracie was a mere 125lbs and had no problem defeating wrestlers 250lbs+. We've got women in our schools that will embarrass alot of guys who think they can fight, let alone average guys.
Dude! i train Brazilian Jiu Jitsu as well! My coach is Evaldo Lima his school is down in Long Beach, Neutral Grounds Jiu Jitsu, Royce just promoted me to blue!