Go on, really shock me! Show me your cardie

When David Dimbleby revealed his new scorpion tattoo last week, there were those who rolled their eyes and implored the 75-year-old to act his age. It seems to me that 75 is the perfect age to get a tattoo: you know your own mind; your parents can't stop you; you don't have to worry about it looking silly when your skin starts to sag; and if you do decide that you hate it, you probably won't have to spend another 75 years regretting it.

As for those who think that the embarrassing intercession of an establishment oldie will "finally" put a stop to this youth "trend" for having tattoos … well, tattoos are sort of the antithesis to a trend. There's nothing fashionable or fleeting about them, either historically or for the recipient.

Dimbleby is not the only one to be told that his behaviour is inappropriate for his age, when really it is completely conventional. Take Miley Cyrus (please, someone). When I hear that something "controversial" has happened involving the 20-year-old former Disney poster girl, I wait to hear what she has done that is out of the ordinary for someone of her age and social bracket, then find she is sticking rigidly to the script.

Last week, she "controversially" smoked a funny-looking cigarette on stage in Amsterdam and tweeted (the outrageous little madam) that "sometimes in life you just gotta decide to not give AF". Bless. She is twerking her little heart out trying to shock, but the whole squeaky-clean teen star turned drug-taking, snarling sexpot thing hasn't really been controversial since Elvis. It would be more shocking if she turned up to a gig wearing a self-knit cardigan.

Then there's Kate Moss, who is celebrating her imminent 40th birthday by posing for Playboy in a position and outfit similar to that shown in the pop artist Allen Jones's woman-on-all-fours Table, which caused such a stir … back in 1969.

Controversial? Maybe, in an attention-seeking and slightly needy "Readers' Wives" sort of way. But, just like when she walked down the catwalk smoking a cigarette in 2011, the most shocking thing about it is that she still seems so desperate to shock.

I sympathise. It must be hard for young people – and approaching middle-age people – to make their mark on a cynical public when it's all been done before. Tattoos are hardly shocking when goody two‑shoes David Beckham is covered by them. A youth filled by inventive and well-documented drug-taking only serves to turn you into Sir Paul McCartney. And it's pretty hard to show more of your body than Madonna did in her book Sex, which was published in October 1992, a month before Miley was born.

However, I think Miley is on to something. Recently, she tweeted that she was up at 2:45am … making her bed "because clean sheets are heaven on earth". Now that's what I call unconventional. Especially if she snuggled in to watch Question Time with a Horlicks and tut at Dimbleby's silly tattoo.

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