Why, at the ripe old age of 57, does Neil Young consistently challenge himself to continue to be one of American music's most relevant and prolific artists? While so many of his generation idle along on farewell after farewell tour, Young has adamantly refused to rest on his laurels and waltz out greatest-hits setlists to appease concertgoers screaming for "Heart of Gold."

This isn't to say that everything Young has touched since his 1972 masterpiece, Harvest, has been, well, gold. As famous as he is for his acoustic folk albums and crazed California garage rock with Crazy Horse, Young’s nearly as infamous for his idiosyncratic genre hopping, starting in 1983 with the vocoder-synthesizer album, Trans. Young’s nightmare attempt at rockabilly, Everybody’s Rockin, followed shortly after the disastrous Trans in 83, resulting in similar critical reaction. 1988’s This Notes for You represents the best of Young’s side trips, mixing soulful r&b tunes, complete with a six-piece horn section, with a few well-penned blues songs. One might even consider 2002’s Are You Passionate? a thematic album in that Booker T & the MGs serve as the backing band for Young's homage to Memphis-Stax soul music.

While Young's current tour-de-force, Greendale, certainly deals with some overarching themes, it doesn’t necessarily represent a specific genre of music as in Young’s past efforts. Written about a fictitious town in Northern California, Greendale is the story of the small coastal crossroads where the Green family resides. Young tells the story of the Greens through individual character sketches in each song- a formula that works well for Young as most of his songwriting is squarely within the storytelling tradition.

The narrative follows the trials and tribulations of Edith and and Earl Green, their daughter Sun, Grandma and Grandpa Green, and cousin Jed Green. Trouble hits Greendale when Jed shoots a local police officer to avoid the discovery of drugs and guns in his car on a routine traffic stop. Jed is sent to jail, and the Green family becomes the target of a mass media blitz, resulting in the on-air heart attack of Grandpa Green as he stands on his front porch, confronting reporters. In the aftermath, Sun Green devotes her energy to fighting the Establishment, be it the corporate destruction of the environment or the monopolization of the media by multinational conglomerates.

The stage production of Greendale is simplistic, with very basic set designs and actors lip-synching the lyrical content of the 10-song, 95-minute performance. Young and the Crazy Horse take center stage, flanked by the Green's house on stage left and the town jail on stage right. A video screen behind the stage reveals a variety of images to the audience, from some very rudimentary set sketches to video clips and close-up footage of the band. A moveable stage sits in front of the screen and behind the band, ascending and descending to display different sets for the actors to work in. At times, the production is pretty hokey, but Young is a Canadian, so we give him the benefit of the doubt. Broadway is safe for now, it seems.

While the stage production may have its professional shortcomings, Young delivers on the musical content on Greendale. Young and the Horse rock out on songs like "Falling From Above", "Leave the Driving", and "Be the Rain", each colored by Young's screaming guitar solos soaring above Billy Talbot and Ralph Molina's rock-steady bass and drums. One of the more poignant moments of the show is during "Bandit", which features Young at his best, alone in the spotlight with only his acoustic guitar in hand. Another high point is the haunting "Carmichael", a rock ode to the policeman killed by Cousin Jed. "Grandpa's Interview" details the media frenzy surrounding the murder and Grandpa Green's eventual demise, with Young spitting dagger lines like, "The only thing good about TV is Leave It to Beaver…Grandpa was fighting for freedom of silence/Just trying to be anonymous." All this played out underneath a video screen with a sketch of a Clear Channel billboard proclaiming "Support Our War." Give Young credit for his ironic wit and subversive distain for Corporate America. Talk about biting the hand that feeds you – Young takes off a finger or two each night the tour hits a Clear Channel-owned venue.

And just when the cries for "Cinnamon Girl" and "Down By the River" have all but subsided, Young delivers high-octane versions of his classics so everyone goes home happy. Sunday night's show featured an enormous "Hey Hey, My My", along with a crowd-pleasing "Roll Another Number" and a third-encore "Powderfinger." Plain and simple, Young and the Horse rock harder than any other band half their age, and they've been doing it for more than 30 years.

Which leaves us with the question we started with: why does Young feel compelled to test the limits of his own creativity in this the twilight of his career? Well, we know he doesn't do it for the money name another artist who refuses to allow albums to be released, despite widespread public demand, because he or she doesn't think CD technology would do them justice. You'll be hard pressed to fine one. And he doesn't do it for the fame, because he's a notorious recluse with no real desire for the national spotlight.

Neil Young continues to push the limits of his music now more than ever because he is compelled to do so, and its unclear whether he cares if anyone "gets it." The confused reviews that have dogged this Greendale tour since its opening night would be a swift kick to the pride of anyone concerned with public acceptance. But as Young once told an interviewer, the success of Harvest's monster single Heart of Gold, "put me in the middle of the road; travelling there soon became a bore, so I headed for the ditch."

Regardless of what anyone says about his various side trips down the slippery slopes of genres as polarizing as rockabilly and electronica, Young is a musical chameleon with the courage to try something new, or in terms of Greendale, to say something that not many people are too keen to listen to. In a time in world history where assimilation reigns supreme, Young remains the outlier, the critic, the harsh voice of reality that kicks us in the ass from time to time when we do something stupid. Rather than criticize his views as outlandish, or characterize his rock opera as a "creative stumble," we should praise the guy for having the balls to stand up in the first place and be counted.

Of course, I've been wrong before. I was one of the few people who bought Trans.