Hehe, I've had this happend to me at least a couple times, and was dieing to try it out as smoker in vs. So they're all back in a group, very nice formation, taking out zombies. Zoe decides to go chuck a molotov, then take a few shots with her assalt rifle. So i latch on to her, drag her through the fire, through the horde, and choke her on a wall. Unfortunately, as I was celebrating Somehow all the survivors were Suddenly Right there and shot me down, still trying to figure that one out.
Also this other time, it was in VS, on the rooftop of the first level in no mercy. Zoey was around the back, and all her teammates were already down the stairs, like far away. So my boomer vomits on her, and she's running towards the outer ledge (like, to the side where the door Isn't), away from the horde, and I just latched on to her (as smoker) and dragged her right back, and she got pummeled like shit, like I was doing 5 - 10 damage a second, and she couldn't do shit. It was hilarious.