It came about after Elton had spent months taking 25 of Rod's greatest songs and writing a story around them, which would hopefully become the musical, Tonight's The Night.
But after Ben finished the script, Roderick refused to read it.
And without his approval, the curtain would never go up.
"Rod said he wouldn't read it because he wouldn't absorb it, so we set up a workshop," recalls Elton.
"I had a feeling he'd like it, and on the 'wonderful' day he turned out, he did and it became a party."
It's taken a couple of months to lure Elton to the tape recorder to talk about his Rod Stewart jukebox show.
But you assume the reluctance is not because he feels he's flogging the theatre equivalent of scratched old vinyl.
This light comedy, Faustian-pact tale of a young garage mechanic, who sells his soul to become a satin-shirted pop singer, has been playing to packed houses for more than a decade.
You suspect, it is most likely to do with the fact that Elton knows, in media terms, he's the man who can do no right.
Despite creating iconic comedy Blackadder, which will re-run until Hell freezes over, he suffers criticism the way the rest of us suffer weather gloom.
It doesn't matter if he's written 13 bestselling novels or his Queen musical We Will Rock You has stormed the world. His theatre work, say critics, is often banal.
But now he's talking. And thankfully, is in fine voice.
"Everything I do comes with a shower of brickbats," he says on the subject of (unfair) criticism.
"Yet, if I avoided a piece of work just because I thought there would be a council truck load of criticism delivered at my door the next morning, I'd never have written anything.
"Apart from my play Popcorn, little I've done has been anything but horrendously received."
He finds it "astonishing" however, that the high-brow critics aren't in tune with jukebox musicals.
"For gawd's sake, who doesn't love a jukebox?" he says.
"Who doesn't look at such a machine either with anticipation - or think 'what memories can I now force on the rest of this pub?'
"Look, the idea that theatre should be a place to be challenged and have one's intellect provoked, well I have no argument with that.
"But why should people who pay the taxes for the intriguing new drama at the National be sneered at for going to the theatre to celebrate a communal experience such as a pop musical?"
Indeed, why not synthesise 25 pop standards with a comic story?
"Theatre has always been about pop music," he continues in animated voice.
"Noel Coward, Cole Porter and Gilbert and Sullivan wrote popular music and used theatre to have their work heard. Now, pop music is coming back to the theatre via the jukebox musicals."
His voice tone lifts in delight: "Can you imagine what it's like for a bloke like me, who spends most of his time alone at a typewriter writing novels, getting to share in this wonderful songbook - and hang out with great actors and musicians at rehearsals?
WHAT you don't appreciate until you see Tonight's The Night is not how many good songs Rod Stewart produced, but how some of his naff efforts such as disco duff Do Ya Think I'm Sexy work when re-imagined with tongue wedged in cheek.
"I'm glad you feel that way," he says, with genuine appreciation in his voice.
"I would never dare to say it myself, but I do think that putting songs in a narrative context gives Rod's songs a different emotional position.
"As the author, it's a gleeful task."
The show has some lovely twists. The Devil, for example, is played by a rather sexy female.
"Hopefully Rod's not been corrupted too much by devils all his life," Elton throws in laughing.
"But I wanted not just to imbue the spirit of Rod's music, which is so deeply romantic, but also to capture his impishness."
And deliver a moral.
"The message is you won't get too far in life trying to be someone else. It's the story of our modern celebrity-obsessed life.
"Just watch The X Factor and hear people say 'I want to be Beyonce.'
"You need to find your own life force."
The cynics argue Elton leapt on to the musical theatre band-wagon. But it's not valid.
When 12-year-old Ben saw Grease in its original London production it was an epiphany. Back in 1973, early in his teens, Elton played the Artful Dodger in a "rather good" amateur production of Oliver!
"I loved musical theatre before it was cool," he laughs.
"There was a time when it was sneered at.
"John Lennon didn't like it, but McCartney did - and I think Paul was right."
HE adds, grinning: "Look, I'm not saying I think the change is down to me, but 12 years ago when I began working with Queen there was a thought that musicals were for grannies.
"Not now. It's a powerful art form. And a joyful one."
The public certainly think so. And since Elton's the man who's put millions of bums on theatre seats, perhaps it's time he got come applause as well.