Last year I had to play-test a Xmas game a lot, because I was part of the dev-team behind the game. I ended up playing it like a robot; I felt I was part of the game's AI. This was a bad thing when we had to record video for the trailer, because the game looked boring out when I played it as a "robot". I simply could not play the game like a normal human being. I tried to fake it so it would look as if I was a real person, but it was very clumsy and I get hit and kill all time in the game. In the end I play the game so bad, that even the game told me I suck at it. It shows that you can play a game too much.