* Alf Clausen simply may not have time to do both the movie and the TV show. They are being produced simultaneously, and the show alone is a full-time gig for many people on its crew.
You could argue that Mark Snow could manage to work on both the series The X-Files and the film The X-Files: Fight the Future, but different levels of energy were involved. Snow largely, often entirely, improvised each episode score on synthesized instruments; he didn’t need to do much agonizing over the overall effect. (This is not knocking Snow’s talent; I think he’s smart and good.) Clausen’s Simpsons work is surprisingly intricate and complicated – it includes (for example) some of the funniest use of musical dissonance I’ve heard on television (seriously) – and is then performed by an ensemble of at least a few dozen musicians. I’ve read interviews; Clausen really sweats it. Snow smartly wrote a more focused and orchestral score for his movie, to “em-biggen” (hey! a Simpsons term!) its sound, but he had the time.
* While I’m an enormous fan of Danny Elfman, his style – always a weird and idiosyncratic one – has evolved so much over time that I can’t imagine him writing 50 or 60 minutes of music that’d sound like it related to the 90 seconds’ worth of theme he wrote for The Simpsons in 1989 (seventeen freakin’ years ago). The closest he’s come to a Simpsons-styled score may be his insane music for Mars Attacks!, seven years after that gig and ten years before now. And a Mars Attacks! sort of score would probably be too heavy for The Simpsons. Something like his droll and dry Men In Black scoring might work…but seriously, let Elfman do something else. (Like his next film, Nacho Libre! Best news I’ve heard today…)
* I’m not so big on Hans Zimmer, but here’s my reasoning about why this could work: Zimmer’s funny. And what’s more, he’s sly. He just doesn’t usually get sly films (would someone who’s seen Madagascar tell me if that film counted as “sly”?), but there’s a twinkle in his eye evident in interviews…or in some of his credits. (Look at the back of the Pirates of the Caribbean soundtrack: “Music Composed by Klaus Badelt. Music Overproduced by Hans Zimmer.”) He’s a big fan of Randy Newman, probably the slyest film composer working now. There’s so much more to Zimmer than Crimson Tide or Gladiator or the theme to The Rock (still a good piece of motivating-myself music, by the way). And he has a working relationship with Simpsons producer James L. Brooks (I’ll Do Anything, for which he wrote something like two-and-a-half or three full scores, As Good As It Gets, and the theme to the TV show The Critic). And I trust Matt Groening’s musical instincts to steer Zimmer towards the most Simpsonian music he can create.
“Simpsonian.” I like that.