Tulisa, Dappy and Fazer of North London pop phenomenon N-Dubz – or, if you prefer, Tula Constavlos, her cousin Dino Constavlos and their schoolfriend Richard Rawson – are easy to mock, and Channel 4 know it. The first episode of this showbiz slice-of-life documentary about the ebullient trio is so slathered with the kind of hideously knowing upper-middle-class arched-eybrow voiceover that characterises the whole of the channel's T4 youth programming strand that you have to wonder if they actually credit the viewer with the ability to form an opinion at all.

You could tell Glastonbury at 40 was in trouble as early as the opening three minutes, when it cut from a well-heeled, ageing hippie survivor mumbling about “earth magic” to footage of Robbie Williams in 1998 bashing his way through the entirety of "Angels". The programme stumbled into the vast gulf between those two concepts as uncertainly as a reveller stumbles into the wrong tent at four in the morning, and never once looked like finding its way back home.

Almost like an inverted echo of Stevie Wonder over in Detroit, Little Stevie Winwood was a Brummie teen prodigy who scored an early dose of stardom with the Spencer Davis Group at age 15. Raved over for his amazing soulful vocals and effortless instrumental skills, he went on to form Traffic before joining “supergroup” Blind Faith with Eric Clapton.

We love Gareth Malone, don’t we? We are big fans of the Pied Piper of primetime. And so we should be. The youth of today seem impressively eager to down tools, put away childish things like knives and drugs and safe-cracking equipment, and follow this slightly weedy and totally uncool choirmaster out onto the concert platform. Our glorious new coalition should be using him to tackle crime.

Remarkably, the most provocative moments in Sir David Frost's survey of TV satire were supplied by his own early-Sixties show, That Was The Week That Was, when he was still an oily young upstart on the make. The BBC's Director General himself had declared that the aim of the show was to "prick the pomposity of public figures", but he must have felt the shockwaves rattling the door of his office.

We know the format: take a bunch of posh, privileged types - held up as examples of cluelessness when it comes to how “ordinary” people live by privileged, overpaid TV executives - and plonk them down in the middle of some dodgy council estate. Remove their credit cards and give them £6.50 to last a week. Watch as they baulk at the amount of cash their new, jobless neighbour manages to spend on fags, kebabs and the occasional drug habit.

American television's desire to upgrade the BBC’s Who do You Think You Are? into a prime piece of emotional real estate was never likely to meet any serious resistance.