Shameless is one of the best dramas of the year: barbed, honest writing, cleverly observed characters and sinewy performances. It is a situation comedy that, thankfully, resists trite situations and cliched comedy. However, the Christmas special demanded a yuletide story and transformed this original piece of underclass-spotting into a sort of Tom Sharpe romp. The tale we got was Now That's What I Call Christianity, a compilation of all the New Testament best bits: births, expulsions, pogroms, rising from the dead, with the army standing in for Rome and the police for the Pharisees. Ultimately, we got a drunken Christ at a Last Supper, neatly, though confusingly, conflating Christmas and Easter. I assume we were supposed to make more of this than just a giggle, but as Brechtian social drama, Shameless shot its own turkey. The half-baked symbolism underlined its intrinsic weaknesses — a deep seam of sentimentality, a voyeuristic attraction for poverty, squalor and dysfunction. It walked a fine line between laughing with and at its characters, between decrying their situation and beatifying it. Its redemption is that it generally stays on the side of the poor and the angels, but this Christmas, it stepped over into farce.

I wonder what Dennis Potter would have made of Shameless. Actually, I know what he would have made of it. He used to sit in this chair. He was a very, very bad television critic. He suffered from the two terminal deficiencies of a wannabe reviewer: he didn't like the medium he had to watch, and he thought he could do it better.

I should qualify that: Potter liked the idea of television, he just hated what was on it. He and the other post-war, first-in-the-family university graduates who flooded the BBC saw television as a Fabian lending library with pictures, a means to educate and motivate the deserving working class. It was also a way of rationalising their guilt at having stepped up into the middle class. They made class and guilt television's abiding theme and became the new inverted establishment, just as arrogant and insufferable as the old one had been.

The BBC is running a festival of Potter plays in the new year. (Michael Gambon, you will notice, has gone from Dennis to Harry.) Some of them are very good, like Blue Remembered Hills and parts of The Singing Detective and Pennies from Heaven; but a lot are pretty dreadful. The initially banned Brimstone & Treacle was dire, and the Orson Welles-ish hubris of Blackeyes was one of the most embarrassing things ever shown on telly. In the end, with his angry working-classness, his crippled hands and his cancer, Potter was an untouchable megalomaniac. After he died, having delivered his own eulogy to Melvyn Bragg, the BBC and ITV got two last posthumous plays that were beyond appalling. After they were broadcast, the Tristrams caught each other's eyes and thought: "We must never let that happen again."

Potter's subject was himself, which is fine, but he wrote about his life as if it were the only one that mattered, as if only his concerns were important. He was vainly, furiously solipsistic and, most damning in terms of the audience, he just wasn't very nice. If you are going to make your life your art, it helps if it's at least a bit likeable. Nigel Williams, whom I admire, made an Arena documentary about
Potter, Painting the Clouds (Christmas Day, BBC2), that consisted mostly of charming but unilluminating encomiums from his family. It wasn't just sympathetic, it was a Stalinist
hagiography, a whitewash that failed to mention either of the posthumous plays and shrugged off criticism, interviewed no contrary voices and touched only briefly on Potter's demeaning and unsavoury sexual history, which would have been okay if Potter hadn't made it so central to his plays. If a writer makes his life his work, then his life should be examined contextually. This biography, whatever its original motive, looked like embarrassing pleading by the BBC on behalf of one of its own, with a bit of licence-fee hymn-singing on the side. I would far rather have had a biography and retrospective season devoted to Jack Rosenthal, who died this year and was a warmer, more humane playwright, someone who liked not only the medium he worked in, but the people who watched it.

Class distinction and struggle are things that happen only in television drama now. They are used as a lazy plot device or a shorthand for char-acter. The awkward social guilt of the box has always been one of its inherited flaws, whether it is favouring a regional accent, targeting some portion of the population or patronising a demographic by making assumptions about its interests and mental agility. Christmas Lights (Monday, ITV1) was a big-budget drama that was, predictably, all about class. What happens to a pair of blue-collar friends when one of them gets a briefcase and becomes management? Most people who have been part of the workforce, which means most people, know exactly what happens: nothing much. We all have friends who do all sorts of things. The distinction between management and workforce has been pretty much irrelevant for 20 years, but not on television. Here, the old cliches of worker solidarity, I'm-All-Right-Jackism and upward mobility are still fresh, and they are shovelled out through the electric hatch like so many Spam fritters. As in Christmas Lights, which was like a reheated Likely Lads with added cancer and Christmas babies. It was nice to see Robson Green and Mark Benton handing in solid, if predictable, performances, and an ironic pleasure to note that this heart-warming, cheek-wetting, toe-curling bollocks was co-written by Bob Mills. It was exactly the sort of programme he would have ridiculed when he was in the comic working classes before he moved up to being a white-collar keyboard-basher.

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