For all his average-lug normality, Garth Brooks does demented like nobody else in country or pop. Every so often in concert and interviews, his eyes bug out and the hammy megalomaniac within emerges. Lately, that tendency has all but subsumed his music: Brooks has become less concerned with stellar songs (see Sevens) and more with gimmicks, like packaging last year’s negligible live album in different covers.

Even in the context of this anything-for-a-headline MO, Brooks’ latest conceit is a genuine head turner. On Garth Brooks In…The Life of Chris Gaines, he’s shed a few pounds, stuck a black wig atop his head, and assumed the persona of a fictitious rock star, ”Chris Gaines.” The album is billed as a ”pre-soundtrack” for The Lamb, a feature film starring Brooks as Gaines. The flick — which has yet to be made — will supposedly chronicle the life of a pop star who’s scarred in a car crash and makes a triumphant comeback. (It’s Behind the Music: The Movie.) Brooks has clearly given much thought to the album, which presents itself as Gaines’ ”greatest hits,” with a bio (he’s the son of an Aussie Olympic swimmer), reproductions of record covers, and liner notes that inform us that one track was used in a pseudo-Armageddon movie called Revelations. And you think Busta Rhymes is loony?

In short, Chris Gaines prepares us for a truly alternative Brooks. Gaines, we’re told, was a huge star in the late ’80s and ’90s. And sure enough, Brooks resembles an aging Goo Goo Doll, while the vintage Gaines ”album jackets,” with their lascivious semi-nude babes, look like outtakes of Scorpions covers. So, we’re led to expect anything from hair metal to imitation grunge.

Instead, Chris Gaines is faded musical wallpaper: mewly, faux-Babyface-unplugged weepers (”Lost in You,” ”That’s the Way I Remember It”) and timid, rinky-dink attempts at blues rock (”White Flag,” ”Snow in July”). Ballads like ”It Don’t Matter to the Sun” are standard Brooks fare, albeit without fiddles and steel guitars. Even the bombastic ”Right Now” — which cobbles together the what’s-wrong-with-the-world sentiments of Cheryl Wheeler’s ”If It Were Up to Me” with the ’60s anthem ”Get Together” — is hardly a radical departure for Brooks, whose records have often been as glossy as middle-of-the-road pop.

The most obvious change is heard in Brooks’ voice. He slips into a sleek falsetto croon here, throatier rock balladeering there, even R&B boy-band harmonies. His singing in each area is proficient, yet has less character than his regular delivery. And would the hard-rockin’, hard-livin’, hard-mascara-wearin’ Gaines actually gulp through a ”Footloose”-style bouncer like ”Digging for Gold”? The music is far too polite and not nearly as fun or raunchy as it’s meant to be. Granted, few acts would risk alienating their audience this way, and the album bypasses the predictability of, say, the career of George Strait. But the gimmick feels as cowardly as it does brave, for it allows Brooks to attempt a pop crossover — it’s his Shania Twain move — without truly committing to it.

Much like the music on it, Chris Gaines is more interesting for what it represents than what it is. From Twain to Faith Hill’s appearance on VH1’s second Divas concert, the new country doesn’t simply want to cross over into mainstream pop; it is pop. While traditionalists remain, the true malling of the Nashville sound has begun, and the movement threatens to strip country of whatever individuality it once had. As for Brooks, perhaps he should have ditched ”Chris Gaines” in favor of a more appropriate trendy rock moniker: Wimp Bizkit.