Kelly sent a comment late Friday to which I couldn't respond fully until now. Her question is insightful and well-reasoned, and deserves a similar response. Here's the best I could do:
Kelly, thank you. Thank you for your patience. I am a big fan of 
competition, in sports, in sales, in most things. The idea of playing a game and not keeping score is ludicrous. The idea of telling a kid she did well when she stunk up the place is ludicrous. But I'm not sure Pollan and Levine are talking about competing. When we compete, we generally have at least some hope of winning. When we compare, we have no chance. We will always lose, because someone somewhere will always be different in ways that we will define as better. We never catch up, and always end in self-pity.
I like your example of a young swimmer, learning to compete. However, I propose that the clock is not the child's competition. Her last time is her competition, the clock merely represents a goal. When she "stops bobbing her head…and swims to the goal," as you say, she is competing only with herself, with her last time, with her old skill. If she comes home deflated that she won just two gold medals when her friend won three, she's comparing.
Mixing metaphors, but the ball is in your court.
