HOW could anyone resist a date with Dame Edna?

Now 79, Edna's creator Barry Humphries has been spreading Everage's waspish love, on and off, since 1955.

Over the years, we've come to love her caustic comments, the way she will mercilessly trash those who interview her and those who work for her.

Such as her constant companion, the silent Madge: "We used to call Madge, Nelson Mandela," says Edna.

"It's because we were never sure if she were dead or alive."

And so the date with the Melbourne-born comedy performer was one to be relished, especially given he's on his farewell tour.

What added to the frisson of anticipation however was Dame Edna cancelled our first date. (Of course it's a woman's prerogative to change her mind.)

"Barry now wants you to see the matinee show, in Edinburgh, before speaking to him," said his management.

Great. Fast forward, and I'm sitting in the circle of the Festival Theatre, about to watch the show and making notes.

Does he need to become other characters? Is he like so many other performers who aren't quite happy with the personality God gave them - and need to become someone else?

Stanley Baxter once revealed he met Humphries at a showbiz party and said that he stayed in Edna character for the whole night.

Is this about shyness, a need to wear a Max Factor and diamante-spectacled mask?

Other thoughts emerge; is he more comfortable playing his drag character than the likes of Sir Les Patterson? Does Edna allow for a stronger comedic voice?

The thoughts are halted; Barry Humphries is now on stage, as Sir Les Patterson, but not wearing the customary drink-stained suit. He's wearing beach wear and it all looks a little forced.

What adds to the worry is the set is a garden scene, with fake grass and hut. There's also a giant hedge and a piano which is covered in grass. It's surreal, but not funny surreal.

What follows is Sir Les's revelation he's now a celebrity chef, and he proceeds to cook on the barbie set up on stage.

And he invites audience members to be his assistants. But as part of the routine Patterson develops chronic 'Montezuma's Revenge' and runs off to the toilet.

While his assistants remain on stage we get to hear Sir Les's bowel movements.

Loudly. The noises continue for the longest time. This is the bottom-line in humour.

The audience, mostly older ladies, stay largely silent.

When he returns, Sir Les proceeds to spray saliva in the direction of the front row. This time, the audience become animated, but it's groans rather than laughter which emerge.

Then Sir Les takes to ranting, which he does well. But there are a few racial references that cause the crowd to take a sharp intake of breath.

At one point he asks if there are any Poles left in Poland. It's a line with no punchline; and you wonder why Humphries has to channel this thought via his character.

Is it his personal reflection on East European migration to the UK?

If it is, you remember he too was once a struggling immigrant who came here to work in London in 1959 and found himself cast as the creepy undertaker Mr Sowerberry in the original production of Oliver!

But then Sir Les outdoes himself; during a comedy song he offers a description of Jews so non-PC the same word recently resulted in Tottenham fans being threatened with arrest.

The notebook flies open and I want to ask Barry Humphries if it's appropriate to revisit Alf Garnett world in this modern age?

Sadly, the first half worsens. Sir Les's 'paedo' Catholic priest brother Gerard emerges (while Les is back in the toilet).

And Humphries' character Sandy Stone offers a monologue that made Ronnie Corbett's dull meanderings seem like a Las Vegas spectaculars.

In the second half however, the lady everyone has been waiting for arrives on stage. Dame Edna is dressed to thrill, and ready for action.

"What was that material before it was a dress, dahling?"

And the little old ladies in the front row love it. Even when on the receiving end of "Look at that face. You could strike a match on it."

One gag however, about Rebekah Brooks was so vulgar it can't be repeated here. (Thankfully it went right over the blue-rinsed heads in the audience.)

And a thought races into the mind; why does this very erudite and intelligent entertainer need to be crude?

Does he resent the fact success has come via Edna?

His mother once dressed him in clothes that were all too girlie. Does part of him wish to rip Edna's ballgowns to pieces?

Barry Humprhies was once an alcoholic depressive, and you wonder if elemental factors of his illness remain?

"I say things other people wish they could say," he claimed in an interview. Mmm. Depends on what you mean by 'other people'.

I also make a note to ask if being a woman on stage is especially liberating; are audiences able to laugh/absorb more from a female caricature than an actual woman?

Did he ever talk to Stanley about this, or Les Dawson?

Another question emerges; has Dame Edna been replaced in the national consciousness by Brendan O'Carroll's hugely popular Mrs Brown, whose comedy creature is both eviscerator and earth mother?

Is this why he says he's calling it a day?

"I want to phase it out while I'm still good at it," he said in a recent interview. "And I am still really good at it."

Five minutes after the curtain has gone down on this two-hour show it's time to meet the man himself.

And it's intriguing. Will he appear as Barry Humphries? Will he be guarded? Will he be likeable?

At the box office, there's a shock.

"Mr Humphries has decided he won't speak to you," says an assistant. "

"You were supposed to go direct to the stage door."

What? And why? Petulance?

Had he been able to read my mind? Did he feel the show had been uneven and disappointing?

What then flashed into the mind at this time was his parting words on stage.

"Will you all do me a favour," says Dame Edna, "and come back for the next final farewell tour?"

It will be fascinating to see how many will.

l Eat Pray Laugh!, The King's Theatre, February 11-15.