But, somehow, when it's the Treasury spokesthing for the Liberal Democrats who is getting hitched to a woman half his age, it all seems less sinister. Malcolm Bruce, aged 53, is not some ageing star attempting to prolong his professional life by bathing in girlish hormones. For a start, in politics it doesn't do to look too young. And Mr Bruce is a well-established sweetie of the kind who wears ties at home on Saturdays.
Yet his marriage later today to 26-year-old Rosemary Vetterlein has brought them both a flood of unwanted advice and unsolicited comments (some of them in this paper) - mostly unsupportive.
Columnists and agony aunts have pointed out that Rosemary is old enough to be his daughter, and - indeed - is almost exactly the same age as his daughter. And they are not over-impressed by the couple's insistence that they themselves are not bothered by the gap. If they are not, goes the argument, then they bloody well ought to be.
I suppose I ought to preface this section of my scribblings by stating the obvious truth that none of this is anybody's business but the Vetterlein- Bruces, and that perhaps we journalists ought to save our advice for those who ask for it. However, the horse is long since bolted from that particular stable, its copious droppings stale on the cobbles leading to the wide world. So maybe the best I can do for Malcolm and Rosemary is to explain why I think they have done the right thing.
In these pages yesterday, the estimable and usually generous Virginia Ironside catalogued the pitfalls that lie ahead of the happy pair, while admitting (grudgingly and in an undertone) that it just might work. And it is, initially, to the items in her catalogue that I wish to address myself.
Item one is the "oldest dad in the playground" argument. All the other fathers, runs this legend, are limber men, bright of eye and fleet of foot. These chaps run races and catch balls with their enchanted offspring, they are vitality and vigour acting as a tonic, chasing away childish enervation. But if Malc and Rosie were to have babies together then - by the time they are in school - he'll be in his dotage. He won't be able to see the ball, let alone kick it. A new verse here for Ralph McTell: Have you seen the old man outside the nursery gates?
But it's all a myth. I'm a dad of 43 and I have never had to work so hard. Consequently, I'm never in the bloody playground. Never mind football, by the time the weekend comes it's all I can do to keep awake while we watch a video together. Yesterday, I barely managed to make it my five- year-old's class assembly because I had to - among other things - slave away at this article.
Had I been 65, though, and retired, I could have stuck around after the performance and congratulated her. What my children want is my time, and when it comes to that, frankly, they would be better off if I was 20 years older or 20 years younger.
Okay lets move on to the inevitable "but he'll die first". Well, darlings, someone's got to. There was a brief vogue in the Seventies for simultaneous orgasms, but they were hard enough to organise - simultaneous natural death must be harder still. So, one partner or the other is going to spend some time bereaved, and which would be preferable: losing your old man when you're young enough to do something about it, or having him snuff it when you are in your declining years and incapable of forming new attachments?
Virginia's most ruthless argument, however, concerns sexual incompatibility. He'll be past it, she says, just when She'll be gagging for it. Now, my first thought is that this is a happy inversion of the usual situation, and will cut out all the headache nonsense. But my second is that the long-term answer is, of course, to have children. Small children depress the libido of even the most rapacious woman almost as much as football does, and for longer. By the time they are old enough to no longer act as a sexual brake, the chances are (as we've discussed) that He'll be dead, and She can look elsewhere.
Finally, I want to deal with the most insidious Ironsidism of all: what she calls "social generation". Old Malcolm, born in the mid-Forties, will have been a young man when the Beatles were in full flight, when San Francisco was the place to be, and when Mick stomped the stage suggesting that we spend the night together. Rosemary, on the other hand, was only six when Johnny Rotten gobbed his first phlegm over Julie Burchill. The gulf is too great.
But this too is nonsense. In the first place, practically all modern hits are simply cover versions of old records. My eight-year-old constantly asks me if I know a newly released song - and I then sing her all the words.
And, in the second, it wasn't just grannies buying Sinatra albums in the shops this week you know.