Shakira, Wembley Arena London Dolly Parton, Wembley Arena London

I'm going to assume that you're not eating your breakfast, and with no apologies charge straight into the phrase "John Major reaching a peak of sexual excitement". Because that, I have to report, is exactly what Shakira sounds like when she makes that peculiar yodelling noise.

Mimicking it is a lot of fun, and passes the long minutes when the Colombian diva isn't shaking her hips, or doing anything very interesting at all. Sadly, there are quite a lot of minutes like that.

If you're going to play a stripped-down, warts-and-all show, fine. If you're going for a stadium spectacular, take the leaf out of... well, Shakira's book last time around (when she entered the stage from the mouth of a giant cobra and rocked out to "Back in Black"). What you must never do, though, is fall between two stools, as Shakira does tonight.

Actually, if Shakira had literally done that, it would have at least raised a laugh. Instead, we get a half-hearted compromise, with a handful of dancers out of a Seventies Turkish Delight ad, a film of the singer doing ballet while someone plays Erik Satie, and a red cape dress operated by wooden poles (which is about as good as it gets). The rest of the time she moseys around in a boob tube and low-slung slacks, warbling in that John Major orgasm way. You can see sticky tape on the floor. Shabby. Almost as shabby as failing to turn up to the very last Top of the Pops when she was No 1 with "Hips Don't Lie".

Not that Shakira's audience mind. If you walked into Wembley unawares, you could be forgiven for thinking you'd entered a Ceausescu revivalist convention, such is the sea of yellow, red and blue flags. If you want real regal pizzazz, though, you have to look to the veterans.

"Tumble out of bed and stumble to the kitchen, pour myself a cup of..." Well, my cupboard's always been bare of that "ambition" stuff, so Ribena will have to do. Dolly Parton, of course, has plenty. You don't get your own postcode by slacking.

Last time I saw her, in the relatively intimate confines of Hammersmith Apollo, Parton was reclaiming her reputation as an authentic country singer. Tonight's show at Wembley couldn't be more different. This is what pays the Dollywood bills. This is Dolly Parton: Showbiz Icon. Which means the hits and the glitz.

Then, as now, she was an engaging presence, always ready with a self-deprecating anecdote. But tonight, I can see that even the ad-libs are on an autocue. We get the full litany: her upbringing among "poor Appalachian farm folk", her father who's never let her get too big-headed, and her mother who sewed her original "Coat of Many Colours".

Nevertheless, when she's on song, Dolly Parton has a knack of making the divisions between alt.country and Nashville seem as preposterously artificial as anything inside her brassiere. The incongruity between her downhome vowels and the billion-dollar bling of her outfits is vaporised.

And when she's not, she's still a fascinating specimen to look at, having indulged in Pete Burns levels of radical body-mod, with her rictus lips, botox cheeks and, credit where it's due, pins to die for. "If I have one more facelift," she regularly quips, "I'll have a beard".

After the interval, we're whisked from Nashville to Vegas, and cover-version hell. In a white trouser-suit encrusted in rhinestones, she leads us through Mary Hopkin's "Those Were the Days", Janis Joplin's "Me and Bobby McGee" and The Byrds' "Turn Turn Turn". Oh, and John Lennon's "Imagine". "Why," she wonders, "can't we just love each other?"

A plea for peace is perhaps understandable. After all, Dolly Parton knows how Oppenheimer feels. She wrote a song which, in someone else's hands, ruined pop for a generation, maybe two. Piloting the metaphorical Enola Gay was Whitney Houston, whose absolute Hiroshima of a cover version, with its grotesquely exaggerated vocal acrobatics, turned "I Will Always Love You" into a smug parade of power and completely overlooked the heartbroken humility of Dolly's original.

Mind you, tonight so does Dolly. She breaks off towards the end of her rendition to tell us a story about the time Elvis phoned her up and asked if he could cover the song. She was overjoyed, until Colonel Tom Parker informed her that the Presley estate would demand 50 per cent of the publishing, and - having already published it herself and had a Country No 1 - she told them to shove it. But, she tells us, the idea of Elvis singing "I Will Always Love You" has always nagged away at her. And at this point...

Well, you had to be there, but when the curtains part, and an Elvis impersonator (complete with fake tan, glue-on sideburns and Aloha Hawaii cape) skips down the staircase to duet with her, most of Wembley is open-mouthed. Some are so appalled that they walk out.

Pure cheese, and it isn't even a classy Italian mozzarella topping, but the rubbery gloop they put on cheap spongy pizzas. The American way, in other words.

s.price@independent.co.uk

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