crowd slipstreaming
Walking directly behind someone who is pushing through a crowd, to avoid having to push through the crowd yourself. Only works if you stay in the empty area directly behind the person in front of you. Usually done behind someone tall or buff.
Guy 1: "Dude, how did you get to class so fast?"
Guy 2: "I did some crowd slipstreaming behind that tall guy over there, it saved me a lot of time."
Guy 2: "I did some crowd slipstreaming behind that tall guy over there, it saved me a lot of time."