Brian Viner: Our in-joke barely makes us laugh now. It's just an instinctive one-liner

Harry Secombe used to sing that if he ruled the world, every day would be the first day of spring, and on Monday, as I motored up the A49 to Ludlow under an intense blue sky, lambs skipping through meadows sparkling with the last of the overnight frost, I knew just where dear old Harry was coming from. I don't think 1 March is officially the first day of spring but in my own personal calendar it always has been; we might still get Arctic weather but I can't think of March as winter. In fact I don't hold at all with a season starting in the middle of a month. Surely, spring is March, April and May, summer is June, July and August, autumn is September and October, and winter is November, December, January and February, which is a bit unfair on autumn but that's Britain for you.

As for motoring up the A49, Monday was one of those days when you simply can't drive through the rolling Welsh Marches, you can only motor. Driving implies a level of concentration on the road ahead that motoring doesn't. When you motor, you have time to enjoy the landscape and perhaps even fiddle for Classic FM. Of course, when you motor, you should also be in a 1957 convertible with the roof down and a beautiful woman in the passenger seat, preferably wearing a woollen headscarf to keep her lustrous locks in order. But you can still motor in a 2007 Volvo, even if the only female in the car is a flatulent West Highland terrier.

Meanwhile, the beautiful woman in my life was on her way home from Suffolk, where she had spent the weekend with old girlfriends from Crouch End. Jane has two annual girls' weekends away, one in late February with the London lot and one in mid-November with her mates from rural Herefordshire. Naturally enough, the Londoners always want to spend their weekends in the country, while the Herefordshire girls head for the towns and cities. Last November they went to Cambridge, and the year before to York, where Jane's friend Ali led them on a search for a wonderfully named medieval thoroughfare that her dad had told her about.

"It's called Knickety-Knackety Street," she declared, and they all marvelled at the quirkily archaic name, before setting off through the drizzle to find it. They looked for ages, even stopping two passers-by who looked as though they knew York intimately, but turned out to come from Antwerp and Minneapolis, respectively. Then they stopped for coffee, and asked the young woman behind the counter. She was from Warsaw, but had lived in York for two years. No, she said, she'd never heard of Knickety-Knackety Street. So off they went to renew the search, until eventually Jane spotted a street sign bearing a quirkily archaic name. It was Whipmawhopmagate. "Oh yes, that's it," cried Ali. "Not Knickety-Knackety Street."

Now, whenever Jane and I are in an unfamiliar town looking for an address, one of us will invariably say, "I think it's just off Knickety-Knackety Street." If we weren't the only people in the western world without a satellite navigation system, we wouldn't be able to crack this in-joke. But can it properly be called a joke? It barely makes us laugh any more, it's just an instinctive one-liner, part of what makes marriage, or long-term coupledom at any rate, such a comfortable state of being.

Coincidentally, on her long journey home from Suffolk on Monday, Jane listened to a discussion about just this phenomenon, on the Radio 4 programme Quote Unquote. That estimable journalist Valerie Grove recalled a James Thurber cartoon that had once greatly tickled her and her husband Trevor. It pictured a barrister in a courtroom, solemnly holding up a kangaroo before a defendant and saying "Perhaps this will refresh your memory". Now, whenever someone in the Grove household has failed to look properly for something, the Thurber cartoon is invoked.

In our house we have loads of these shared-experience one-liners, extending well beyond Knickety-Knackety Street to "use it as a rudder", "Jackie Charlton", "awful people" and the gnomic, "one thing's for sure, they won't be going back to Zimbabwe". There's no room to explain why, and you probably wouldn't want to know anyway. But if you've motored with me through this column, here's a one-liner we can share: if I ruled the world, 1 March would be the first day of spring.