Off Kilter, BBC4<br/>Tweed, BBC4

A little bit of tartan and a gimlet eye: With jokes so good you forget to listen, Meades hits the Hebrides, while a toe-curling moment shows old tweed unravelling

It's a decade since Scottish devolution, and the country's government has shown that it has come of age by handling the al-Megrahi affair with all the judgement and precision of a whisky-sodden highlander tossing a caber into a Morningside tea party. But that's a terrible Caledonian cliché, two in fact, and such assumptions won't do in BBC4's Scotland season. Particularly under the gimlet and shaded eye of Jonathan Meades.

For Off Kilter, Meades is touring Scotland in three episodes. The week before last, he took his Deputy Dawg features to Aberdeen to celebrate its granite edifices. On Wednesday, he skulked in Stirling, the home of his grandparents, to prick the tartan balloon of the Scottish roots experience. He then hoved to on the wild shores of Lewis and Harris island, far to the north-west, to ponder a more complex definition of Scottish origins.

It was classic Meades, suited, booted and plonking himself into landscapes and seascapes, towns and villages to deliver a typically acerbic polemic, aided and abetted by the usual mischievous visuals. But familiarity with his style doesn't make the mix any less rich – a little too rich sometimes. To watch him in full flow is the telly equivalent of chewing on a wedge of Stornoway black pudding washed down with a triple malt. At one point several Meadeses lined up in mimicry of a Neolithic stone circle, while the man himself wondered whether the circles were "pre-Euclidean exercises in creating a non-representational kind of art". Try to get that down you without a belch or two.

Occasionally, the visual jokes were so good you forgot to listen: one sequence showed sea eagles catching fish with black letterboxes superimposed over their eyes, like murderers caught in the act. I'm sure Meades cranked out some sharp one-liner or other about savage nature over the top, but I've no idea what it was. All I can recall is that brilliant sight gag.

He ranged over far too many subjects to dwell on here – the island's particular geology, its awful architecture and the drug-dealing baronet who once owned Lewis and Harris and helped to start the Opium Wars. This is clearly a programme to be digested on iPlayer several times over. I caught it only the once, and God knows where Meades was meandering with his collection of footnotes, engrossing though they were. He scolded those who like to cloak the stone circles of the island and elsewhere in druidic claptrap – if anything, these were signs of early scientific experiment. He noted its strong Calvinist orthodoxy – 50 churches for 22,000 inhabitants – and wondered, on an island he unashamedly calls paradise, why the locals persisted in a religion that "incites us to lead a life in fear of life".

Finally, he looked upon the island's rusting car wrecks and agricultural machinery and saw a nightmare vision of the future, a world where communities seceded and retreated into ever more narrow cultural identities to the point of social collapse. How the hell did he end up here? I've no idea, but it was 58 wonderful minutes from a wee bit of tartan to the end of the world.

Lewis and Harris, Meades pronounced, is suffering an "aesthetic bereavement so absolute that it is a sort of insouciant anti-aesthetic". He may have been describing the fate that had befallen Harris's most famous export, as detailed in Tweed, a three-part examination of the island's attempts to rescue its centuries-old textile industry. One of the island's biggest tweed mills had decided to scrap thousands of its famous patterns and push just four – one, fashioned into a grim, monotone grey jacket, was modelled awkwardly by a mill manager, and in that toe-curling moment you could see how a deep a hole the mills had to climb out of.

I know, a series on the plight of tweed hardly sounds like cutting-edge commissioning, but the result is an enjoyably mild parable of British industry. With one episode to go, our cast includes a bluff, ageing textiles magnate seemingly intent on destroying Harris's heritage single-handedly, a gaggle of metropolitan designers who flock to the island (one of them in mauve and purple tweed cape, jacket and matching plus-fours) to try to re-establish lines of supply, and the Harris Tweed Authority woman, who makes the local sheep look like ruthless, self-starting go-getters. At the moment, the bemused locals are doing little more than shaking their heads beside their looms, and trying to forget about Jonathan Meades.