In the wake of Ashlee Simpson's lip-synch debacle on SNL nearly two years ago, Kelefa Sanneh wrote a diatribe against its most strident critics in The New York Times. "The Rap Against Rockism" asked "Could it really be a coincidence that rockist complaints often pit straight white men against the rest of the world?" (A rockist, of course, being a subscriber to the creed of authenticity and a strict guitars-drums-bass worldview.) In other words, is "alternative rock," in all its monikers, yet another white boys' club defined by its own exclusivity?

Coachella, a documentary on the six-year-old Indio, California music festival of the same name, incessantly begs such questions by refusing to play to its strengths. The slim target audience for a film like this asks only for the opportunity to catch some of the great performances, which steep ticket prices seem calculated to guarantee they'll always miss. Forty-five minutes of pure music would have done nicely. Instead, director Drew Thomas delivers a hippie-inspired paean to the restorative and political power of music.

One moment speaks volumes. After everyone from Perry Farrell to Flea has praised Coachella for its commitment to music in the face of Corporate America, the focus shifts briefly outside the confines of the Indio playing field. Thomas approaches a group of probably indigent black men and women who, looking for a place to fish, had stumbled unwittingly across the sprawling mass of the festival. The scene is almost comical, if not for the unsettling racial undertones. The juxtaposition of these outsiders against the tens of thousands of white indie rockers, out $200 for their tickets and talking about peace, love and saving the world, could be ironic, if only the filmmakers had such a discerning eye.

Noel Gallagher offers some respite when, in reliably foul language, he scoffs at the notion that music is anything more than entertainment. Too bad every saccharine shot of the sun gleaming off the picturesque field works to convince the audience otherwise. Coachella, as a film, is not as actively exclusive as the "rockists" Sanneh indicts, but it similarly ignores reality in favor of a delusional glorification of rock and roll. When Noel Gallagher is a voice of reason, something has obviously gone terribly wrong.

The actual music ranges quite a bit. After an overblown lead-up in which a chorus of musicians sing their praises, Iggy and the Stooges run through an underwhelming performance of "I Wanna Be Your Dog" that leaves them seeming rather dated. On the other hand, Radiohead's "Planet Telex," featuring a deliciously manic Thom Yorke, proves the band is worth every word of praise ever printed. The Flaming Lips may have stolen the show, with lead singer Wayne Coyne rolling out into the audience in a huge plastic bubble. Many of the other major names (Oasis, Red Hot Chili Peppers, Belle & Sebastian, White Stripes) are good, but ultimately forgettable. With each artist confined to a single song, it's difficult to know whether to blame lackluster performances or poor song selection by the filmmakers.

In the end, what should have been a concise concert film is instead a two-hour, neither-here-nor-there feature punctuated by some inspired musical moments. For these gems, Coachella may be worth renting, but if you want to drown out the sound of self-important voices, be prepared to hit fast-forward or head to Indio yourself.