There can be no doubt that this is a seismic week. For it marks the departure of Carol Vorderman from Countdown, after a quarter of a century of quickfire maths, increasingly chic dresses, and accidentally racking out the word “UPARSE” after taking one from the top, and three from the bottom.

On One Last Consonant Please Carol Channel 4 pays tribute to Vorderman's long service. You don't need an IQ of 167 to guess that this comes in the form of hilarious outtakes, a montage of Carol's worst outfits, someone from Dictionary Corner making a slightly leery comment about Vorderman's legs, and Carol accidentally racking out the word “UPARSE”. I am having to guess, however, as there were no preview discs available of the show - despite there, theoretically, having been 25 years to prepare them.

Again, having not seen the show, one can only speculate on how such a presumably light-hearted endeavour tackles the undeniably awkward conclusion of Vorderman's tenure: the sudden death of Richard Whiteley, Vorderman's protracted mourning (“I was devastated. I became aware of my own mortality. [Now] I write poetry.”), plunging ratings, Vorderman's fee be-ing slashed from £1million to £100,000, her indignant resignation, and then Vorderman's rapid replacement with a foxy blonde 22-year-old maths graduate from Oxford. It's kind of hard to cobble an upbeat conclusion to that lot. I've got to admit that if I were the director of One Last Consonant Please Carol I would get to, say, 2002 in the narrative, have a voiceover say “And then we woke up, and it had all been a dream,” and then quickly run the credits.

Immediately after One Last Consonant Please Carol comes Vorderman's swansong Countdown. Again, no discs available here - just the information that the Dictionary Corner wizard, on this momentous occasion, is to be Gyles Brandreth - a man so facetious that even students don't pretend to like him ironically. However, 33 years of watching television tells me that - after dabbing at her eyes with a tissue a great deal - Vorderman must almost certainly end the show by spelling out “GOODBYE” on the Countdown Word Board, with one letter left over on the end. Perhaps a “P”. “GOODBYEP”. And then leave for ever.

Personally, I find the whole issue of Carol Vorderman and Countdown a vexed one. Countdown is a show I should, theoretically, love. It's a shambolic, low-fi Victorian parlour game broadcast at teatime, in which people do anagrams with paper and pencil. If it hadn't already been invented, I would be lobbying Parliament for its inception on a daily basis.

And yet - and yet, I sodding, f-word loathe the show. It rankles me, right in my pituitary. With its ticking clocks and awkward half-jokes, and its anxious anticipation of the next, ultimately pointless, task, it reminds me of every awful childhood Sunday, right up until they reformed the Sunday trading laws in 1994, and MTV started broadcasting on Sky. It tastes of dust and virginity. It crawls at the pace of an ailing rock. Really, Victorian parlour games are fun only when everyone around the table is half-cut, wearing paper crowns on their heads at jaunty angles, and secretly wondering if the next round will end in rampant wife-swapping. Even when everyone really cuts loose on Countdown - on an end of season finale, say, or when they have a spooky-amazing 12-year-old Sikh kid on - it never has that air.

And much the same goes for Carol Vorderman. In theory, I'm all gung-ho for a nerdy maths chick who does a Reverse Midlife Crisis, chucks off her sensible cardies, and starts foxing it up at premieres in dresses cut up to here. That sounds great.

But when it comes down to it, Carol Vorderman was a wildly over-patronised relic of a pre-feminist era (“A WOMAN! Who does MATHS NUMBERS!!!”), who ultimately crunched all her supposed intelligence down into the single biggest decision of her life: “I will pay for my house by flogging debt to peasants on the FirstPlus adverts.”

As the credit crunch kicks in, and her more easily influenced fans start to really savour the full extent of consolidating all their debt into a second mortgage while the housing market crashes into negative equity, I, personally, think it's for the best that Carol won't be around for a while.

One Last Consonant Please Carol, Friday, Channel 4, 2.55pm, followed by Countdown, 3:25pm

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