Once, of course, the standard refuge for the harassed viewer would have been situation comedy. Twenty years ago, the schedules were awash with the things, some making us laugh, others making us wince and a select few, such as Love Thy Neighbour, making us violent. But that was 20 years ago. These days sitcoms compete with Barbary leopards and Faberge eggs for rarity value. Take last week. In a week where the need for amusement became almost pathological, how many sitcoms do you think there were on our screens? That's British-made sitcoms, on any of the five terrestrial channels, that hadn't been shown a thousand times already. How many?
Two. One on BBC1 (Goodnight Sweetheart), one on ITV (Loved By You). None on BBC2 or Channel 4, and certainly none on Channel 5, which hasn't even commissioned one. Two sitcoms in 800 hours of non-stop broadcasting. And they are both on at the same time.
What a pair. Loved By You (ITV, Tuesday) only just qualifies as British, even though it was made over here by Carlton and stars two very British actors in John Gordon Sinclair and Trevyn McDowell. Its scripts, however, are American, bought in from the current US hit Mad About You (shown most days on Sky One). When American TV buys British sitcom formats, it remakes them in its own image - perfectly reasonable, if you think about it, although galling for the writers who fashioned the original scripts.
When British TV buys American formats, by contrast, it changes nothing. The odd joke is anglicised, but the original script is otherwise untouched. You end up with an American sitcom performed by British actors in British accents, and sounding like nothing on earth.
Mad About You was about an attractive young couple living in a loft apartment in New York and gradually coming to terms with married life. Loved By You is about the same couple, now British and living in a one- bedroom flat in London. This is no ordinary one-bedroom flat, however. Carlton, as well as duplicating the jokes and the situations, have also duplicated the set, which is about the size of Blenheim Palace. The bathroom alone would sell for pounds 120,000 on the open market, and the living room would be ideal for five-a-side football. Young this couple may be, struggling they ain't.
Everything is slightly wrong. McDowell's lines sound pure Jewish New York, even though she is clearly about as Jewish as Mother Teresa. "What happened to the rebel of yesteryear?" asks Sinclair's best friend. "Listening to Dylan, going to demos, maaan
You only have to watch Mad About You for five minutes to know that this was never going to work. Like so many American shows, it's sassy, confident, aspirational and thoroughly pleased with itself. Most British sitcoms that find an audience are gloomy, bleak, ironic and steeped in disappointment. Loved by You resides in a cultural void of its own making. And it's ITV's only sitcom.
Straight-faced, we turn to Goodnight Sweetheart (BBC1, Tuesday). Now in its fourth season, this Laurence Marks and Maurice Gran construction has grown increasingly abstract. The options for a time-travel comedy in which a feckless hero enjoys relationships with women in the 1940s and the 1990s were never extensive, but Gary Sparrow's gradual realisation that he is never going to be caught has brought the series' dramatic thrust, such as it was, to a virtual standstill. Accordingly the vast team of young writers Marks and Gran employ now appear to approach their task primarily as an intellectual challenge. Keep it going, just keep it going, and pray that no one notices it has nowhere actually to go. Every wild plot variation must be called into service to secure the only genuine challenge left to the show: to be recommissioned for yet another year.
For four years, then, Victor McGuire has played Ron, Gary's best friend in the 1990s and deliverer of most of the script's best lines. But this week he also played Ron's grandfather in the 1940s, who astonishingly looked and talked and acted just like Ron. Would the course of history be changed? As it hadn't been in the preceding 50 or so episodes, it seemed reasonably likely that it wouldn't be this week. And so it proved. As Gary, Nicholas Lyndhurst breezed through as usual, now obviously resigned to the knowledge that he will never get another role as satisfying as Rodney Trotter. And this is the BBC's only sitcom.
We should probably blame such enterprises as They Think It's All Over (BBC1, Thursday). Ridiculously cheap and dead easy to make, comedy quiz shows have supplanted sitcoms in all too many schedules. Channel 5 broadcasts little else, while the BBC is so happy with Nick Hancock and co that it has commissioned them for two series a year of 10 episodes each for three years, and even then they'd prefer more. Meanwhile the dark clouds of critical backlash threaten. We have seen Never Mind the Buzzcocks, and we wish we hadn't. We have heard of Channel 5's medical-comedy quiz-show, Tibs and Fibs, and determined to avoid it. And we have watched as the stars of They Think It's All Over have cheerfully embraced the lucrative distractions of celebrity. Adverts, hopeless spin- off sitcoms, not very amusing stand-up shows - these boys have done it all. You would hardly blame them if a certain complacency were to creep in, a sense that there was nothing much else left to prove. In other words, everyone is just waiting for them to blow it.
So for the show to keep up its standards as it has done is no small triumph. Consistently teetering on the brink of self-indulgence, it is in fact a remarkably professional piece of work. Nick Hancock's scripted links (written by others) set the tone, but Hancock himself is a wonderful host, constantly provoking and geeing up the others with immaculately timed ad- libs. It's also a skilfully edited show, ruthless in its pursuit of the good gag. The Christmas before last, the team produced a 40-minute special that, for the first time, revealed the slack inherent in the format. It's not a mistake they have repeated. At 30 minutes They Think It's All Over remains an amazingly reliable source of laughs. Of how many other current shows can you say that?
Which brings me, with some trepidation, to Mrs Merton in Las Vegas (BBC1, Thursday). Here is another show that teeters, this time on the cusp between mockery and embarrassment. Caroline Aherne's character is an intriguing creation - a satirist's spoof of a pastiche of a parody - and that she has found a home on nice mainstream BBC1 is remarkable enough. But if ever there were an example of a comic idea overreaching itself, this was it.
With 50 members of her regular audience in tow - a feat of organisation rather more interesting than any of the programmes - Aherne could only actually find four Hollywood stars willing to be interviewed. This week, Patrick Duffy mucked around and flirted, Tony Curtis flirted and mucked around, and Aherne looked nervous and out of place. Such a joke obviously doesn't travel easily - many of her cultural references had to be explained in painful detail to her guests - but there had already been indications in previous weeks that the series was running out of steam. All the guests now know what to expect, which at least halves the point of making the show in the first place. And has there been anything in this run as funny as her British Gas commercial? Mrs Merton's next career move should probably be into sitcom. If anyone is still making them, of course ...
David Aaronovitch returns in May.