If nothing else, with Mylo Xyloto, Coldplay may have succeeded in making the least conceptually developed concept album of all time.

Chris Martin and bandmates have described their song cycle as being about two young lovers who come apart and fall back together in the face of the oppressors that perennially conspire to keep youthful romantics down -- like, you know, rock critics and GOOP-bashing player haters.

Sorry, had to go there. No, Mylo Xyloto actually appears to be set in some future dystopia, where underdogs in love rage against the machine by… spray-painting.

That's as specific as it gets, and any listeners not clued in ahead of time that there's an ostensible narrative arc will be none the wiser -- or sorrier -- for not noticing that songs like Us Against the World refer to characters named Mylo and Xyloto (pronunciation key: rhymes with so-so) and not Martin and partner(s).

Take away that thin post-prog-rock story hook and what's left is prototypical Coldplay: vague but soaring anthems of undying hope and passion, set to modest piano intros that build to cathedral-sized synth blasts, with choruses whose sing-song-y lyrical conceits may or may not eventually just give way to the falsetto oh-oh-oh-oh-oh that everyone's waiting for.

There are slight wrinkles in the sound, but not as many as promised. Which is a shame, because on the band's two previous albums, they really did make some headway, with X&Y finding harder guitar edges to balance out the electronic piano trademark, and Viva la Vida or Death and All His Friends successfully expanding into orchestral and exotic-instrument eclecticism.

But now that Death has taken a holiday, Mylo Xyloto comes off as a retreat back into familiar safety zones, even as it holds onto some of the last album's Enoxification (with Brian Eno credited this time as a co-writer and aural consultant, but not officially a producer).

Pre-release promises about changes to the sound don't add up to much. Martin had described the album as Coldplay's move into pop, which is a little like saying that Jimmy Cliff is thinking about trying out reggae.

Even more ballyhooed were the supposed dance-music influences, which you might search for in vain, unless the occasional rave-like tone of the most underlying synths counts.

Only one track really goes there, that being -- naturally -- the duet with Rihanna on Princess of China, which features RiRi singing a lot of whoa-oh-oh-oh and la-la-la-la in the choruses, per the inclinations of her host. In the outro, though, Martin and Rihanna join together to repeat the line You really hurt me, and it's a half-startling moment, since there's not much in the way of vivid pain that comes through anywhere else on this aurally over-cushioned album.

On Viva la Vida, Martin seemed to be making some strides toward slightly darker territory, especially with the uncharacteristically lustful Yes. But on Mylo Xyloto, he refrains from identifying much of anything interior that might be pulling his lovers apart before they get it back together.

Maybe Martin's too much the eternal idealist to ever linger in shady places. Or maybe he's just too intensely, defensively private, knowing that anything much in the way emotional specifics would have fans (and haters) scouring the lyric sheet for clues to his highly guarded relationship with a famous movie actress, something he could never stomach.

What you're left with on the frustrating Mylo Xyloto is, to be sure, pretty -- often, really, really pretty -- but as hard to get a hold of in its smaller moments as its would-be concept is to grasp as a bigger picture.