Every incarnation of this franchise, from the comic book to the TV show to the video game, insists the walkers are stupid creatures; rotting bodies with rotting brains. But how does that explain the multiple cases of ambush you encounter throughout the game?
I didn't keep count, but there were close to a dozen incidents when a zombie would simply lunge out from some convenient hidey-hole, or even play possum before a convenient human passed by. One of the moments you can't alter no matter what you do (namely Lee's bite) is a huge example of this at work.
Could someone directly involved with the series please make a statement about how smart or dumb the walkers really are?