Smarter people than me have talked about how Twitter and other social media feeds engage our brains much like a slot machine—every pull to refresh gives a small chance of hitting the jackpot—rage, dunks, laughs!—but most of the time just offer low-grade tedium. And yet we keep pulling down. Yglesias strikes me as a sort of micro version of this same addiction model—most of the time he gives us pablum, but there’s always a small chance of a big payoff! The repetition is definitely part of the formula, but so is the chance of serendipity.