The collapse of a portion of the "American Idol" stage left the Final Four performing without the benefit of a full dress rehearsal. But surely the sage vocal coaching of Slash would be sufficient to steer them to solid Classic Rock Night performances?

Click through for recaps of the four solo performances, plus what I can only pray will be the first and last use of "American Idol" competitive duets...

Singer: ADAM LAMBERT
Song: "Whole Lot of Love"
My Take: After an extended guitar intro, Adam breaks into a Zeppelin cover that is every bit as glam-rock-perfect as you'd imagine, but is it too conventional a Robert Plant impression? This is perhaps the most straight-forward performance Adam's given all season. I mean, he's utterly tremendous within the carbon-copy parameters and if Plant ever wants to take a vacation, he could tour with Jimmy Page. It's not a karaoke performance, but it may be a stadium-touring cover-band performance. I'm still disappointed we didn't get to hear Slash and Adam jamming on some G-n-R classics. You think they could "blow it out da box" on "Mr. Brownstone"? Because I'd watch that.
Georges Clemenceau, Vittorio Orlando, Woodrow Wilson and Simon Say: This is the Adam that Randy loves, as the judge reassures Adam that he's a rock star, not a Broadway star. Kara clarifies that Adam is actually a Rock God. Poor Kara. She's auditioning for a role on the "Gossip Girl" spinoff tonight. Paula raves that Adam is "A whole lotta perfect." Simon complains that the performance was understated. It's one of Simon's favorite Adam performance and he warns that nobody can top it.

Singer: ALLISON IRAHETA
Song: "Cry Baby"
My Take: Allison reports that she went to Adam's hair-dresser this week and it's a big improvement. We've had our share of Janis Joplin impersonators in recent seasons, but Allison thankfully doesn't aim for a strict cover. It's been properly arranged, so that it starts high enough that she doesn't get lost in the early going. And when it gets to the chorus, you best believe Allison gets to bellowing. My read is that it's too clean and not really all that emotionally invested. But it's certainly technically proficient, if a smidge one-note.
Georges Clemenceau, Vittorio Orlando, Woodrow Wilson and Simon Say: Check it. Randy reassures Allison that she can sing her face off, but that this wasn't the right song choice for her. Kara agrees that Janis was fine, but that this wasn't the song she'd have chosen. Paula confusingly says that if they ever do a biopic on Janis Joplin, she's got the role. Would that complete head-to-head with Jenna Maroney's Jackie Jormp-Jomp biopic? Simon didn't see all that much original in the performance. There ensues a confusing conversation about what song Allison should have picked, leading to the most spirit and talking back that Allison has done all season. Too little, too late on the personality?

Singer[s]: KRIS ALLEN AND DANNY GOKEY
Song: "Renegade"
My Take: I'm not saying this duets nonsense is the worst idea the "American Idol" producers have ever had, but we're down to the Final Four and we shouldn't be wasting our time on what is essentially an exhibition performance. Because why would I care whether or not Danny and Kris can sing Styx together? Yes. They're harmonizing nicely. But who cares? I'd rather just listen to Adam sing this song solo, which he'd do better than either of these two individually or together. Or is that the point? If I'm going to listen to a Styx duet, I want it to be courtesy of Jeffster. The song has been arranged much too low for Danny, who sounds horrid at first, shouting his way awkwardly into the melody. Kris sounds better, but again... Who cares? They don't have inherently compatible voices and the combination of the voices doesn't do anything to improve the song. And why would this make me want to vote for either of them individually?
Georges Clemenceau, Vittorio Orlando, Woodrow Wilson and Simon Say: Randy loved the harmonies. Kara mumbles something incoherent, as does Paula. Simon says Danny beat Kris. Ah, yes. Truly capturing the spirit of a duet. I don't object to duets per se, but in the future I'd like to see them do this on a Wednesday, rather when they're supposed to be bucking for votes.

Singer: KRIS ALLEN
Song: "Come Together"
My Take: Carly Smithson did a really solid job with "Come Together" last season. Does Acoustic Wonderboy Kris really want to go down this path? It's a bit of a jam band version of "Come Together," which makes it the edgiest thing Kris has done to date. Kris was enunciating last week, but he mumbles his way through the lyrics of "Come Together" and I define covers of this song by how much fun the singers have with the twisted wordplay. Kris doesn't have an iota of fun. You darn well better believe that Adam would have done something twisted with the lyrics. It's hard to exactly pick out how much of the music he's providing on his guitar, but he seems to be part of the band, which speaks well for that aspect of his performance.
Georges Clemenceau, Vittorio Orlando, Woodrow Wilson and Simon Say: Randy knows that Kris isn't the rock guy, but he appreciates that Kris did something where he got to be himself. You know what he loved, though? Kris' guitar work. Kara thought it was trying too hard and that it wasn't the best song. Paula loved Kris' "artistic delivery," but wanted a little more energy. "It was rather like eating ice for lunch," Simon says, perhaps echoing last week's "wet" comment. Simon calls it a jam. That's what I thought!

Singer: DANNY GOKEY
Song: "Dream On"
My Take: Hey look. It's another rock song where all I can do is think of how well Adam probably would have done it and how unremarkable the alternative is. Honestly, are we going to say that Danny's Aerosmith is appreciatively better than what Michael Johns did with the same song last year? No. He's got melody problems early and then has trouble when the song breaks away from the traditional rhythm. It's shout-y, not sing-y, especially the shrieking that was supposed to be the musical highlight. We're supposed to be impressed and all I could do was think, "That makes *my* throat hurt."
Georges Clemenceau, Vittorio Orlando, Woodrow Wilson and Simon Say: It was only aight for Randy, but he still gives Danny an A+ for effort. Kara thinks Danny took the judges' advice to add more swagger, but he went too far. Did Kara tell Danny that he should be trying more early Aerosmith. Earlier than "Dream On"? I miss Paula's comments boggling over Kara's latest bit of confusing idiocy. "It was like watching a horror movie," Simon says of the last note. Danny didn't think it was as bad as the judges said it was. "It's... whatever," he says.

Singer: ADAM LAMBERT and ALLISON IRAHETA
Song: "Slow Ride"
My Take: Ah, Foghat. If this were a Wednesday show, this is exactly the duet I'd want to watch. Not only to Allison and Adam have interesting contrasting vocal styles, but as a musical theater guy, you know that Adam is ever-capable of stepping back and adding harmony and letting his co-star shine. Danny and Allison together, for example, would have been a disaster. But Adam is able to bring out the best in Allison's vocals and also in her personality. They end in a big hug that's tremendously sweet. This should be the Top Two, America.
Georges Clemenceau, Vittorio Orlando, Woodrow Wilson and Simon Say: It was da bomb for Randy. Kara tells them that this was a duet that was right, that they pushed each other to be better. Paula thinks this was the perfect marriage. No comment, Paula. No comment. "In the battle of duets, you win the show tonight," Simon says. Simon suggests that the Adam Halo may keep Allison in the competition.

TONIGHT'S BEST: Given my drothers, I'd have listened to six Adam Lambert performances tonight. Yes, I said it was too straight-forward, but it was straight-forward GOOD. Ballgame over, kids.

TONIGHT'S WORST: My throat will be raw all week just from listening to Danny Gokey.

IN DANGER: I think Danny's in the bottom, but Allison has cheated death too many times. She wasn't bad tonight at all. In fact, with Adam, she was great. But will that duet actually be able to save her and send Gokey home?

Agree? Disagree? Who do you think is going home tomorrow?