Billy Connolly, Usher Hall, Edinburgh

The show's a bit fragmented", warned Billy Connolly within the first few minutes of his latest and typically well-sold Scottish tour, "because I haven't worked in ages".

This is, you get the feeling, what most of his fans expect. Despite recent and extended diversions into film acting and travelogue television, Connolly's immense popularity at home and among the Scots diaspora in New Zealand, Australia, Canada and the US is still based on the image of him as the shaggy-haired wild man, ranting and swearing and going into detail about his own bodily functions during a show.

In which case, it's unlikely that the audiences which face him on this tour will be disappointed. At the age of 66, Connolly's flowing beard and hair have turned a fine, distinguished white, and they form an uncharacteristically monochromatic look alongside his black T-shirt and black-and-white striped trousers.

There's something almost self-consciously youthful and punkish about this outfit, but the non-smoking, non-drinking Connolly ("I've become the type of person I used to avoid") still moves around his stage with a healthy, excited enthusiasm.

For many among the expectant crowd, his way with a spat-out epithet is an end in itself, and for those of a less easily-offended nature there's something graceful, almost poetic about the way he swears.

An extended meditation on the correct way to refer to a hopeless plumber as a "prick" is hilarious, but also precisely considered and constructed with grace. It's like music, says Connolly; three beats of silence before the offending word carries all the effect.

Those who criticise Connolly are best advised to do so having seen him live, rather than basing their opinion on what they find in the media and on his edited live recordings. He says the unpalatable and occasionally unsayable, but in the context of the rest of the show everything finds its justification.

The "c" word appears, for example. "I know it's an uncomfortable word," says Connolly, "that's why I said it". He takes great glee in doing so casually, but expresses displeasure at the way he finds it commonly used in America; directed forcefully at women with bitter misogyny.

Without getting all Richard Herring about it, Connolly has deconstructed the layers of meaning and intent behind a swear word which turn it from just another piece of vocabulary into something far more unpleasant.

Not that this point will have impacted on the majority of the audience in anything but an unconscious way. Instead, they would have found an almost cathartic sense of communal recognition in the drunk Scotsman waiting outside a Rose Street pub, practising his first line to the barman who barred him, or the "heavy-breather" Connolly met in a Dumfries chemist waiting to air his grievances about Bonnie Prince Charlie.

Since Connolly recently moved back to Scotland for at least part of the year, he has fully re-engaged with the national mindset – full-flow and clearly heartfelt tirades about the "sneaky bastards" in Parliament (both Holyrood and Westminster) who outlawed smoking but have ensured that they themselves still have their own smoking room, and about the contentious issue of the Edinburgh trams raise the biggest ovations.

Never has swearing or ranting been so masterful and well-considered as here. The bits about bodily functions, on the other hand, can be taken at face value.

Touring to 4 October (www.billyconnolly.com)