It's useful to be able to analyze a game, checking what's interesting in it, good or poor, what could be improve, what you can learn from it, what mechanics may be useful in another context...
By using this template, you train to go through a game while having a closer look on its structure. A game designer is not only a player and should be able to say more than "Well, this game is pretty cool or it sucks!" and by so to learn from any existing game.

The first rule is to differenciate the game play, the game system, the formal elements of the game from technical, graphical and editorial dimensions. Keep the focus on the game system, you're in front of.
Second simple rule: Play! Play! (& write down all comments or ideas) A game analysis can't be done without several playtesting sessions. Analyzing a game without playing at it, it's like talking about a movie you have'nt seen!

Template for Game Analysis