I keep forgetting to write this post, but a number of correspondents and colleagues wrote in about this post on Taylor Swift and her collaboration with Swedish songwriters to say that I should have clarified that Swift herself is a credited co-writer of "22" and, indeed, is listed as either the sole author or a co-author on all the tracks on Red. Apparently there's a longstanding gendered practice of disparaging the contributions of woman musicians—particularly younger ones—to their own work, and a lot of people saw me as playing into that by wanting to highlight the contributions of Max Martin and Shellback.
Those are well-taken points. My larger point, though, still stands that there's a kind of odd convention arising out of rock music that the ideal is to be making a recording of yourself playing a song you wrote yourself, ideally as part of a band composed of your longtime buddies. In other fields of endeavor we generally recognize the virtues of specialization, professionalization, and the division of labor. Airpline pilots don't build airplanes, and the guys who build airplanes don't design airplane engines. And selection of collaborators is itself a skill. Most nice restaurants have a pastry chef with a specific area of responsibility but hiring the right guy for the job is itself part of the job. Swift is a big star and she can probably work with who she likes. If she works with great people, that's every bit as much a credit to her as if she does great work by herself.