I feel your pain. I HATE it in BB when you get stuck with sucky teammates who wouldn't know common sense if it hit them in the head. I once played a round in the Outpost and was on the Janus team, I grab the BB and start heading towards that big overhang on the building with the satellite, you know the one. I get it about 3/4 up the stairs before getting killed, so I head back, but another teammate beats me too it. But he doesn't continue going up the stairs. Oh no, he starts heading down the stairs over to the building where everyone always camps in the upstairs room. Of course, we lose the game because he brings the box right out into the open again.
And it's even worse when no one on your team knows how to shoot. If I'm trying to hack a console and a low-level teammate with a Kallos Grenadier is guarding me. I can bet you my life's savings that if someone rushes in and starts shooting while I'm still hacking, my teammate won't move, let alone shoot, or make any attempt to protect me, leaving me to interrupt the download in order to save my own ass.