For the last six weeks, I have been trying to write something about Valve’s Left 4 Dead, unsuccessfully. This is because our site is about Overthinking stuff, and a post called “OMG ME PWN ZOMBIES!!” would not be appropriate. (Besides, everybody already wrote that review when the game was released, including the New York Times.) This game unleashing a feeling in me I can only describe as “Wheeeeeeeee,” which makes overthinking hard. But I’ll try.