The Duke &ndash; A Portrait of Prince Philip, ITV <br />Abortion: The Choice, BBC2<br />What Happened Next?, BBC4

It was a road trip like no other. They hit the track and didn't look back till they got to, ooh, the edge of the Sandringham estate. Behind the wheel, squinting at the horizon, exuding irritation through every pore, was the dude they call The Duke. Sitting in the passenger spot, squirming, trussed up in his seatbelt, poor Sir Trevor McDonald eyed The Duke nervously. This was less like a buddy movie, more a hostage situation. To try to calm The Duke, everything McDonald said was prefaced by "sir" and delivered in amiable, pacifying tones. It didn't work. Dukey was on a hair-trigger. Anything could set him off. Even a grazing hind: "Ghastly little deer!"

It was delightfully uncomfortable viewing, but at least this sequence felt fresh, which is more than can be said for the rest of the stiff, airless documentary The Duke – A Portrait of Prince Philip. Pre-recorded tributes flowed in thick and fast, some of them more plausible than others. "He's fun, he's flirty and he's a game, game guy!"

"The Duke of Edinburgh was someone who brought verve and dynamism to our university at Edinburgh," offered Gordon Brown. Sadly for Edinburgh, I think he meant it. When Brown was elected rector of the university as a student, the Duke supported him more than most. But the real problem with the Prime Minister's contribution was that it was couched entirely in the past tense. It seemed to have been filmed with an eye to another, less happy occasion.

Usually, royal documentaries fill you with pity for their duty-bound, formality-shackled subjects, pit ponies working for the preservation of unfashionable values and their own dynasty. But this time it was different. Prince Philip's life looked utterly enviable, a concatenation of leisure activities. Painting (he's inspired, get this, by Gauguin). Cricket (dutifully, he's played with the best). Travel (the sacrifice!). And founding sadistic award schemes that make young people get blisters and eat mud. (Sorry, I still haven't got over my Silver Orienteering experience.)

When we tell ourselves that being royal is a Faustian pact, who are we kidding? Attending all those ceremonial functions seems a small price to pay for the life of Riley.

Abortion: The Choice was a documentary that is part of a BBC season called "Bare Facts". But it contained very few facts at all, clothed or otherwise. Instead its tenor was emotional. Recurring keywords were "heartfelt", "instincts" and "feelings". It would have been a lot more interesting – and potentially useful – if, instead of this subjective mush, we had heard more about the practicalities of abortion, both as a decision and a process.

Despite the fact that the programme centred around the Marie Stopes clinic, it wasn't mentioned that they charge £60 for a phone consultation and between £390 and £1,600 per procedure. How their services compare with those offered by the NHS was also deemed off limits. Instead, we were given a dreamy dramatic reconstruction of the time one woman wandered into a church, just to think for a bit. We were also treated to comments such as this: "Not many people go into it [abortion] without a lot of concern, care, worry and turmoil." The dangerous implication of this was that if you weren't torn up by the procedure, you really should be. Then there was some portentous music and some more tearful interviewees. Why no positivity? This programme downplayed the beneficial, uncomplicated aspects of abortion to a degree that was, I thought, highly reprehensible.

Anyway, hey ho, and thank goodness for What Happened Next?, an inspired new BBC4 strand that revisits old documentaries and shows us where their subjects are now. It combines assiduous new research with great archive truffling. Who says TV is a medium with amnesia?

The first programme looked at the 1973 documentary about the Global Village Trucking Company, a hippie band who eschewed the tyranny of record labels and lived together in a country commune, skipping through fields semi-naked, tooting flutes.

Close-ups of their young, lean long-haired selves dissolved into close-ups of bald old men. The flowing locks had gone and so had many of the attitudes. A couple who once rejoiced in communal living were now settled in bourgeois splendour. One woman, Danielle, who had appeared in the documentary naked in the bath, revealed that her grandmother hadn't talked to her for three years afterwards. Other band members, however, were still living the dream. One was pioneering colour holography, another living in the Beshara School of Intensive Esoteric Education. Most remembered their experiences with the band as magical, and "inspired by a lot of LSD". No mention of drugs had been made the first time round. Do time and distance bring candour?

Or has what you can and can't say on television changed? What Happened Next? is a series set to provide profound insights into how both individuals and culture change over the years. It's time-lapse photography on a human scale.