Beer Can Chicken: Is it Really Better?

Q: Will grilling chicken on a beer can really make it better? 

A: Every year around grilling season I get into conversations about the best methods for grilling chicken. And inevitably, somebody says the magic words: "beer can chicken." 

Is there some magical alchemy going on between the beer and the chicken? What exactly makes that chicken come out so moist? 

To test this, I cooked four chickens side by side: the first with a beer can, the second with an emptied beer can filled with water, the third with a can filled with Mountain Dew, and the last with a completely empty can (I added a few pebbles for ballast). If it was the alcohol doing something, I should detect a difference in the beer-cooked chicken. If it was the liquid, then the can with pebbles should be significantly different, and if there was some flavor exchange going on, then Mountain Dew would surely stand out, right? 

Guess what? The four chickens were pretty much indistinguishable. 

As it turns out, the reason beer can chicken is juicier is not because beer vapors magically penetrate them; it's simply because the method puts the legs closer to the heat source than the breasts, which allows the breasts to cook more gently, minimizing moisture loss. Moreover, the can insulates the interior of the chicken. As for the can's contents, believe me: That beer will do a better job in your belly than in the chicken's.