On Saturdays in this paper My Week appears, a column in which I pretend, I hope humorously, to be someone else. One Friday, about a year and a half ago, I pretended to be Baroness Thatcher.

At the time of writing, I was pretty pleased with it. I was jet-lagged, mind you, having spent a hellish night on a flight to Bombay, but I still felt that I'd done OK. They had just unveiled that bronze statue in the House of Commons, and I had Maggie as a doddery old dear, not quite remembering what sort of Lady she had been, but being darned sure it wasn't a bronze one. Some of it was nasty, but there were also some good jokes. I was pleased with the one about David Steel.

So I finished it, yawned, and e-mailed it to the office. And it never went in the paper. Because it was vile.

The next night, still jet-lagged, I stared at the ceiling for a while, torturing myself with what might have happened otherwise. These senior editors at The Times, they know their stuff. It had, indeed, been vile. Not 30,000 complaints vile, surely, but vile enough. Lucky me, for having editors. That's the problem with trying to be edgy. Sometimes you come down on the wrong side of the edge.

So far, so obvious. Jonathan Ross and Russell Brand went too far; they were vile, and somebody should have stopped them. But that's only half the story. Why do so many people care? Is it because Ross earns so much money, and we all have to pay? Partly. Is it because everybody loved Fawlty Towers? Again, partly. But there is something else going on, too. Something more personal. I think it is shame.

Once upon a time, I reckon, there was a great gulf in this country between public humour and private humour. Public humour is the stuff that you get in newspapers. Maybe on Radio 4. Private humour, that's more vicious. It's the way you talk in the pub. It's the “oh my God, I can't believe you shagged her” sort of humour. We all do it, or most of us do, but we wouldn't want to explain it to our grandparents. They wouldn't get it. They'd think we were scum.

Recently, maybe in the past 20 years, the one has bled into the other. That's why some things are “edgy”; because they sneak vicious, irony-laden private humour out into the public sphere. Little Britain, The Office, Mock the Week, all that. Brand is entirely edgy, Ross, a bit less so.

It's a newish sort of comedy and the skill lies in navigating the vile. Or suppressing the vile, if you prefer. You don't really mean the vile bits. You don't mean any disrespect to the people you are being vile about. You just use them, to chase the laugh.

Audiences have grown pretty good at understanding this. For younger ones, it's instinctive. For others, it's a guilty pleasure. Only we wouldn't want to explain that to our grandparents, either. And that, I think, is why some of us are so angry. That was Ross and Brand's big crime. They involved grandparents. They betrayed the Great British conspiracy of vile.

Lost for woods

It's a silly thing, but in the midst of all that, I very nearly used the phrase “can't see the wood for the trees”. I didn't, in the end, because I suddenly realised I didn't have a clue what it meant.

Conventionally, you see, “wood” would be a synonym for “small forest”. As in, you can't see the big picture, because you are so busy looking at the details.

Although, as I wrote the words, it occurred to me that “wood” also means, you know, wood. The stuff of which trees are made. So, if you couldn't see the wood for the trees, this could also mean that you are totally missing the details, because you are so busy looking at the big picture. This is the opposite situation entirely. It's a thoroughly irresponsible idiom.

This, just so you know, was my honest attempt to write a short piece of humorous prose without being remotely vile about anybody. I thought it was going quite well. Although, looking into the origins of the phrase, I now learn that it was first used by the playwright John Heywood, in 1546. So I suppose I've ended up being slightly vile about him. The git.

Politics by Dawson's Creek

It may be a personal oddity, but I tend to enjoy party political broadcasts. I like the way they are rubbish. Disappointing then, to sit through Barack Obama's latest half-hour election broadcast without sniggering once. It was disarmingly perfect. Heart-rending, sepia-toned stuff, all windswept wheatfields and soothing, reverb-heavy soundtracks. I thought the glockenspiel was overkill, but maybe that's just me being pernickety. Beautiful stuff. Like a montage from Dawson's Creek, as compiled by Tom Hanks.

British efforts are far more fun. My recent favourite was the one that the Lib Dems squeezed out, during their last party conference. whenever they went to one of their little case studies, to the working, black, single mum, or the old white guy complaining about waiting lists, a little tag came up underneath that said “ACTOR”. It made them look of limited appeal, although also rather fabulously glamorous.

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