But playing in these sophisticated surroundings as part of the Meltdown 99 Festival only seemed to egg Sir Les on to ever more gross extremes. He was like a naughty schoolboy, unable to suppress the urge to swear in front of the vicar. Sir Les himself admitted: "I know a lot of you are asking what is Les Patterson doing in a beautiful venue like this? And I tell you, I'm asking the same question."
Sir Les is the ultimate one-joke wonder - in his search for material, he rarely sees the need to stray far beyond his own orifices. But it is a joke pulled off with such panache that it scarcely matters.
From the moment he marched on stage last night after Nick Cave's fulsome introduction and asked, "Who was that tall streak of piss?", we knew we were not destined for a night of exquisitely subtle wordplay.
The audience, however, simply lapped up the stream of single entendres, most of which are too rude for reproduction in a family newspaper. I could not, for example, begin to recount what he produced from his trousers during his duet with Kylie Minogue. Nor would I contemplate repeating his explanation of how the Poet Laureate came to be known as Andrew Motion.
Barry Humphries' creation may revel in his image as the man political correctness forgot, but it is hard to resist a performer who takes such obvious joy in language. For instance, he called a hard-drinking friend "a card-carrying turps-nudger who bugles the bottle". Sir Les savours words like drops of amber nectar.
I could easily have lived without Sir Les's songs, and there was a ghastly crashing of gears as Germaine Greer came on in an academic gown to read out a ribald poem by the Earl of Rochester.
A garnish of kitsch was provided by a leather-clad Rolf Harris - yes, it was that kind of night. Dame Edna Everage also made a sparky appearance, breezing in for just long enough to insult a woman in the front row about her frock. "It's a lovely fabric. You were lucky to get so much of it."
But it was Sir Les's show. As he exited, the audience whooped and hollered with a fervour rarely heard within the hallowed portals of the Royal Festival Hall. Is Sir Les Patterson the greatest Australian export this side of the cricketer Shane Warne? No worries, mate.