Led Zeppelin's failure to trash any hotel rooms during their latest comeback will have had some fans longing for the glory days of rock, when the destruction of hotel furniture ranked alongside 30-minute drum solos as an essential part of a band's performance, writes Frank McNally.
Similarly, the news that Robert Plant asked only for a mug of tea and an ironing board - so that he could press his own clothes - before this week's London concert will have struck some old hippies as poignant confirmation of the veteran rockers' decline.
By contrast, their new-found wholesomeness will be welcomed by Christian conservatives, who can at last give up trying to find Satanic messages in the band's music. The theory used to be that, when played backwards, the lyrics of Stairway to Heaven encouraged devil worship. Which of course fitted with the group's former hell-raising habits of throwing television sets from windows, and not doing their own ironing.
I confess that, at an impressionable age, I used to think the words of Stairway to Heaven meant something when played forwards. I suspected there was a hidden message in such lines as "Your stairway lies on the whispering wind". Pending enlightenment, I would sing along with Plant: "Ooh, it makes me wonder." But by early adulthood, it was clear the search was hopeless.
It's good that the surviving members of Led Zeppelin are ageing gracefully. At least they can still play their music. Whereas I was saddened recently to see that another late 20th-century icon, former Soviet president Mikhail Gorbachev, has been reduced in his retirement to advertising suitcases.
There he is, on the back page of the latest issue of the New Yorker, pictured in a taxi with a Louis Vuitton travel bag on the seat beside him and the tag-line: "A journey brings us face to face with ourselves." The line is a reference to the Berlin Wall, a surviving stretch of which provides the backdrop, seen through the taxi window.
As I surveyed Mr Gorbachev's now haggard features, memories of his greatest hits - including "Glasnost", "Uskoreniye" and, of course, "Perestroika" - came flooding back. Who could forget that wild night in the late 1980s when he trashed the same Berlin Wall? Or that whole heady era when, in a feat no hell-raising rock band has ever come close to, he managed to break up the entire Soviet Union? Now here he was, in old age, selling his baggage in more ways than one. All right, apparently, an unspecified donation from his fee is going to an environmental charity. Even so, the small print at the bottom - "Mikhail Gorbachev and Louis Vuitton are proud to support Green Cross International" - looked like a fig-leaf for his dignity.
This is not Gorbachev's first foray into advertising. In 1997, he famously raised money for his Perestroika foundation by shooting a commercial for Pizza Hut, one of the companies whose tanks rolled into eastern Europe when the wall came down. So, if not exactly dignified for a former world leader, advertising designer suitcases could at least be seen as a step in the right direction.
But wait. Is it possible that there is another, deeper motivation behind his latest campaign? Could the ad have a subliminal political message if - for example - you looked at it upside down? Yes! Or at least maybe. Because it turns out that the half-open case beside him has a Russian magazine tossed casually on top, with a headline in Cyrillic script. Turned around, blown up, and translated, this reads: "The Murder of Litvinenko: They Wanted to Give up the Suspect for $7,000." The reference here is to the former KGB spy, assassinated by radiation poisoning in London last year, who on his deathbed implicated the current Russian President Vladimir Putin in the plot. Britain wants one of Litvinenko's former associates, Andrei Lugovoi, extradited for questioning. And the magazine's story was that secret police had offered reporters information about Lugovoi's whereabouts, for a fee.
When rumours about the ad started circulating on the internet, the producers dismissed the notion that it had any hidden message. So did Gorbachev, who said he hadn't even noticed the magazine's contents during the shoot. But others weren't so sure.
"In an industry where sesame seeds are hand-placed on a hamburger bun by food technicians before a shot, one would reasonably assume that this was not something that happened by chance," a top marketing expert told the New York Times.
The counter-argument is that the Litvinenko story just happened to be in the current issue of the magazine when the picture was taken (last May) - and that, anyway, internet conspiracy theorists will find intrigue wherever they look. Which is true.
No doubt the famous birthmark on Mr Gorbachev's forehead, or at least the graffiti on the wall behind him, is still being combed for the name of the murderer.
The head of marketing at Louis Vuitton insisted that if the message had been deliberate, it would not have been placed "upside down, in Cyrillic, and in need of a magnifying glass to be read". And he's probably right. But ooh, as Robert Plant says, it makes me wonder.