Because that's what Parkinson has become: a Holy Grail of quality television (a status that last year's repeats of classic shows only confirmed). After Parky vacated the interviewer's chair, traditional chat - the world of Wogan and Aspel - seemed as moth-eaten as a pile of old jumpers. Enter the new chat, the David Letterman-inspired blend of stand-up comedy and cheeky questions, which in turn has influenced shows as diverse as Ruby Wax and Clive "yakkety-yak-don't talk-back" Anderson.
By the time Danny Baker gave his take on the Letterman format, it already had one foot in the grave. "Basically," said Channel 4's Seamus Cassidy, who commissioned The Gaby Roslin Show, "it [Danny Baker After All] was a photocopy of a photocopy of a photocopy. And it was made by people who had forgotten the importance of the host, people who didn't know the difference between irony and contempt." All good knockabout stuff - Channel 4 executive lashes BBC rivals - but a touch ironic after 12 months in which Channel 4 has given us Chris Evans's TFI Friday and The Girlie Show with Rachel Williams (what was that about the importance of the host?). If the modern chat show is in disrepute, Channel 4 has as much to do with it as anyone.
For a programmer trying to halt the downward spiral of soundbite-based talk shows, there's a lot to be said for Gaby Roslin (and very little that anyone in the business will say bad about her). On The Big Breakfast, she exuded both confidence and warmth, whether interviewing a Hollywood film star or a woman with 37 cats, who'd just won the lottery. Surprisingly, for anyone blonde and female and in front of the camera, she has managed to avoid the bimbo tag. It comes as no surprise that her father, Clive Roslin, is a Radio 4 presenter. But are these admirable qualities enough if you want to emulate Parky in the Nineties?
After all, the reason Aspel and Co sank without a trace wasn't its presenter but the insatiable demands of media-savvy celebrities and their agents intent on plugging their latest products. Anyone who saw the infamous edition on which the three founders of Planet Hollywood - Arnold Schwarzenegger, Sylvester Stallone and Bruce Willis - plugged their theme restaurant with utter contempt for either their interviewer or the viewing public, will have some idea of the problems that the chat-show host in the Nineties faces.
When Rod Hull's Emu attacked Parkinson it made great television because it was so unexpected. Today, it would be nothing more than another stunt, an advert for Emu videos or Emu steaks. Faced with watching weekly advertorials, Aspel and Co's audience deserted the show in droves (ratings fell from a peak of 10 million to 4.5), and its presenter walked away in disgust. The last show that made any attempt to pull the plug on plugging was, incidentally, Danny Baker's. Come back, hairy one, all is forgiven.
With these cautionary tales in mind, let's turn back to the as yet untarnished ideals of The Gaby Roslin Show. "The aim," says its editor, Andrew Davies, "is to return to guests who have a story to tell and let them tell it in full, rather than in you go, gag at your expense, quick plug and out the other end. There's a genuine need for it now. People are fed up with the Clive James/ Clive Anderson format, where guests sometimes just seem to be there as fodder."
Davies wants interviewees who will "set the news agenda rather than react to it" and complains about insulting audiences "by assuming they don't have the ability to listen. It's 9pm on Saturday. People have stayed in. They want something they can concentrate on." Guests scheduled for the first show include Ike Turner and Eddie Izzard (neither of whom are at present on the plug); and Elton John and David Duchovny - Agent Mulder in The X Files - are being lined up as a double-act later in the series for no better reason than they are, apparently, great fans of each other.
At the end of the day, however, primetime TV needs stars and stars have a tendency to make their own rules. And whether by week 10, Roslin and her team will still have the will to follow their instincts, rather than taking orders from the Hollywood publicity machine, remains to be seen. Only then will we know whether the ghost of Parkinson has finally been laid.
`The Gaby Roslin Show', 9pm tomorrow C4