Credibility? The Simpsons Sing the Blues was recorded in 1990, about 10 months after the show debuted as a half hour program. This effetively pre-dated all credibility the Simpsons ever had
I could, and I was surprised by how good the song was, considering what it was. Sure, Michael Jackson produced it on the crapper, but you can still hear it. The fact that he produced this really explains his early "guest appearance" on the show, and becomes strangely troubling when you consider the fact that he was only interested in the Simpsons when it revolved around a prepubescent ten year old boy from an abusive home.