Most of Saturday's show was a broader, more robustly funny affair than the Lake Wobegon narratives. The Royal Philharmonic, nonconformist as ever, had advertised its South Bank season as opening with a 'recital for mixed baritone and orchestra', and the Keillor voice is certainly a thing of some variegation, quavering with 'sincerity' but getting the melodies neatly through the microphone.
There was no contest between words and music: his big opera number was the 'Habanera', as written by Duane Bizet from Omaha. 'I know what they're singing,' he announced of opera in general, 'they're singing about adolescence,' and he reconstructed half-a-dozen of the most typical operatic characters - among them Ophelia, suggesting that his experience of opera is more recherche than most people's.
Talking, though, had the edge on singing. Keillor's classic number is The Young Lutheran's Guide to the Orchestra ('Lutherans are like Scottish people, only with less frivolity'). The idea is that music must remain a limited experience for the truly devout, as one by one the instruments reveal their worldly or immoral associations. Only the angelic harpist and the patient, rest-counting percussionist escape. The secondary joke is that each section has to keep a virtuoso variation going while the audience collapses at the targeted wisecracks. The RPO's horns appeared to find this more amusing than the bassoons.
Some of the targets are indeed missed - trombones as 'thickeners, like cornstarch'. This is an outsider's humour about music. Really musical humour, such as Hoffnung's, never does that; nor would it put up with Randall Davidson's bland, inoffensive scores. (The conductor, Philip Brunelle, who timed everything tightly, supplied some rather sharper links and backings of his own.)
But that is to reckon without Keillor the performer. At the evening's climax, he left the orchestra silent and launched out alone with two of his Lake Wobegon tales. It takes a supreme storyteller to have a packed Festival Hall hanging on every word for half an hour. That's why he is a radio natural, too. Television would only cut the hot-line from voice to listener's imagination.
You do not have to like him to fall for him. The stories of small worlds and empty lives are touching but indulgent, their irony soft for English tastes. A couple of the songs hovered on the edge of mawkishness. 'We are what we are,' he said, summing up. And Keillor is the extraordinary one, the one who got away from Wobegon.