Sid Meier, who doesn't make puzzle games, has a saying that everyone who does make puzzle games has probably thought about from time to time. Actually, it's more of a question. A challenge. To paraphrase, since I am stupid and have lost the exact wording, Meier likes to ask his team: Who is having fun here? Voila: the question as hand grenade. Is the designer having most of the fun? If so, what about the player?