The baroque goofiness of Blackbird Spyplane’s house style can be something of a test for readers of the newsletter (the “sletter,” in Blackbird Spyplane parlance). “X out of ten people are going to show up and read that and just be like, This is impenetrable, I’m out,” Weiner told one interviewer. “But for the people who stick around, I think that it adds to a sense of, Oh, this is like an in-joke that I’m in on.” And better (at least to this reader) that clubbiness take a niche form — it is less claustrophobia-inducing than the many newsletters that seem to insist we are all wearily following the same disputes on Twitter, all inevitably watching the same shows on Netflix. Such newsletters wind up feeling like crowded rooms with too few windows on the world beyond.