This exercises the happy path, but otherwise works surprisingly badly for testing. You already know what the game is supposed to be about, so you can't really t

This exercises the happy path, but otherwise works surprisingly badly for testing. You already know what the game is supposed to be about, so you can't really tell how well the interface communicates things to someone who doesn't, and you more or less automatically play it the way you're "supposed to", so you rarely hit the sorts of buggy or game breaking corner cases testing is supposed to discover.