The old showbiz saying goes you don’t mess with a winner. The only real difference between this new series of The Adam & Joe Show and programme’s early days is that the wily pair have got more money to play with – which simply means the good bits are extremely good, and the iffy bits almost unbearably bad, but we’re cleverly still left with fascinating, rewarding television.

It doesn’t feel like this show has now been running for almost five years; or that thanks toTakeover TV (bizarrely due for a new series later this year) Adam and Joe have enjoyed a screen presence that stretches back almost a decade. In part that’s down to some of the elements of this Show wearing well and not appearing unnecessarily outdated or too predictable.

But while the bedsit’s OK because they keep changing the junk that covers the walls, one obvious obtrusion arrives in the very first frame: the laughable voiceover and slide that still announces “Warning: The Adam & Joe Show Is A High Density Programme – Start Taping Now!” This is a real throwback to the mid ’90s – specifically to Fist of Fun, where you really did have to start taping to enjoy the spoof credits. It calls attention to itself because it’s the first thing up on the screen, and as a reminder of what was alternative way back before the Showwas really that well known.

So far this series Adam and Joe have usually offered up one or two isolated sketches or stunts in-between the pastiches. Not this week however; here were 30 minutes completely filled up with parodies and piss-takes, which in turn neatly highlighted both the strong and weak points of this enduring format. So least impressive was BaaadDad Undercover, a showcase for Adam’s dad who this series is spoofing Donal MacIntyre in some shock exposés of popular culture he still knows so little about. When Nigel Buxton first showed up on this programme his hapless attempts to even understand a new record, let alone the Glastonbury festival, were great comedy moments. Now the concept wears thin. This week the man simply attended a school as if a normal teenage kid; nothing of consequence followed, either really funny or particularly annoying. The result: just aimless telly.

But talking of which, far and away the best bit of this show was a class parody of Chris Morris’jam. It’s instructive to reflect on how much fuss this programme generated when it first aired – and then how quickly the froth blew away. It didn’t take long before those carefully taped episodes were casually wiped with something else. Adam and Joe paid tribute via a spot-on imitation of the show’s silly content, its arrogant stylised production and editing, and the suspect motivation of Morris himself. Even the willfully obscure ambient soundtrack was there, plus the obligatory visit to the surgery (“Doctor, I … I feel like a pair of curtains …”) “That’s just revolting – my Mum’s gonna watch this,” complains Adam; “What about my genius,” protests Joe, “you don’t understand my genius!”

The regular soft toy spoof excelled itself this week thanks to a combined rip off of both The Jo Whiley Show, Loose Women and Richard Blackwood, all within a parody of Late Review. Bumbling bore Mark Lawson became Humpty Lawson (“I must say I thought it was quite brilliant”) while ranters Tony Parsons, Alison Pearson and Tom Paulin were turned into a monkey (Tony Peanuts), a pig (Alison Porcine) and the brilliant Tom Tortoise with perfect laconic Paulin-style voice and mannerisms. The Jo Whooley Show itself starred Fran Squealy (“Music’s like this box of red balloons with ‘Hello’ written on them”) and Moosey Gray (“I dunno about balloons and all that stuff, I just think spiritually, y’know, you gotta … what was the question again?”) Tom Tortoise then expressed surprise with his support for The Richard Blackdog Show (“Who’s the dog?”) but true to form, “just as the programme started to get interesting we’ve run out of time.”

Another high point was People Place, “the show that goes wherever there’s a place with people in it”. Here not just the content but the whole look and feel of that generic non-descript morning TV lifestyle consumer magazine nightmare was caught to perfection. We had bustling hosts not listening to any of the members of the public, pointless features, crappy idents, nauseating music, plus those po-faced aphorisms – “They say apples are the root of all evil, but that can’t be true, can it?” All great fun, and far removed from those amateurish features of the earlier series both filmed by and starring Adam or Joe involving just a camcorder and some Beadle-esque tricks.

The whole show was blessed with a special theme – the Shock TV Special – with links featuring footage of Joe with needles poked through the top layer of skin on his fingertips, or Joe holding up “a human heart”. We also had spoofs of Eurotrash – “Can you believe the sauce of these Amazons!”; Robot Wars (Toaster Wars) and your Melvyn Bragg smarmy arts strand in Omniken. TV buffs would have been pleased with the spoof idents for both 1970s BBC1 and London Weekend Television.

It might be an obvious seam but Messrs. Buxton and Cornish are still mining it with enough enthusiasm and imagination to turn over a higher rate of hits than misses. The pastiche 1980s House which ended last week was a complete success, once again thanks to the care taken in every detail of how the scenes were filmed, the music, even the guest appearance from Leeee John. Sometimes the additional time and money the pair have been allowed encourages self-indulgence; the Star Wars rip-offs, with real mouths superimposed onto replica models, are almost too professional and clever-clever. Waving a cuddly toy in the camera lens still produces more of a gut laugh.

There’ll come a point when Adam and Joe get too old for all this, and it’ll be a sad day when that happens, though at the moment they still look as young as they did when they first appeared. Their bedsit’s safe for a while, and there’s always a career as a full-time professional talking head on a Saturday evening TV nostalgia package once they turn 35.