Reclusiveness
Swartzwelder is a notorious recluse and rarely, if ever, makes media appearances. At one point fans of The Simpsons on the internet debated his existence, combining his reclusiveness with the number of episodes credited him, and theorized that "John Swartzwelder" was actually a pseudonym for when writers either did not want to take credit for an episode or else episodes penned by several writers in concert.
He has also famously not participated in any of the audio commentaries on the The Simpsons DVD sets to date, despite being asked multiple times. Executive Producer David Mirkin even offered to have him make a brief appearance in a prerecorded bit in which he would be asked if he wanted to take part and he would respond, "No," as an ironic punchline, but he refused. During the recording for the ninth season (released December 2006) episode "The Cartridge Family"'s commentary show runner Mike Scully called Swartzwelder's home on the phone. After speaking for a few minutes with him (presumably), the man on the other end of the phone ended the call by saying, "It's too bad this really isn't John Swartzwelder".
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