When it arrives, we're in full complimentary flow about the dapper singer-songwriter's excellent new album Out Of The Game. Trendily pitched as 'Wainwright goes pop!', in truth the project's a honeyed mesh of Elton'n'Nilsson vintage-isms and daring, swooping melodies - all uninterruptedly modernised by the neoteric sheen of Mark Ronson.
We're not sure if it's playfulness, sincerity or sheer weariness that drives Wainwright to inject such an early jolt of libidinous cheek into our chat - but when he portrays the hormonal stimulation that Ronson inspired in his studio performance, he leaves us close to blushing.
"We kind of fell in love with each other," he reveals, half-draped over the sofa of publicist Barbara Charone in north-west London, clad in a typically natty check suit and trainers.
"There's a real attraction between Mark and I, which is a little harder for me being gay. I have to battle with it. Whether it's the Beatles or the Stones or Eurythmics, there's an unrequited sexual, romantic energy in the studio - and it becomes volatile if not dealt with.
"To have someone to sing to and dream about in that amorphous state is what it's all about in the end. People fall in love with people - yes, there are gay people, straight people and bisexuals. But crushes are universal."
And to think we wanted to talk about streaming monetisation and direct-to-fan initiatives.
Turns out there's plenty more gossip provocation in Wainwright's media arsenal, too: not least when we dig a little deeper in the singer-songwriter's motivations for some of the strikingly acerbic lyrics on his consistently sweet-sounding seventh studio LP. ("Look at you suckers/Does your mama know what you're doing?")
"I think a lot of it has to do with Lady Gaga, to be honest," he replies, dejectedly tipping his brow skywards. "I totally admire her tenacity, her ambition and her strength of vision. There's just not one good song there.
"People, especially gay men, are falling so hard for it. Certain things that [she] says: 'Look at me. I was like you one day and now I'm this - and you can do it too.' I find it a bit disingenuous. We are in this somewhat sinister period and [artists have] got to kind of toughen up and be real. I guess I want to put a little bit more grit into my presentation of what's happening in the world. It's about conveying what's inside us, as opposed to the return of the cone breasts. I find it predictable and boring."
Predictable and boring: labels even the most ardent Gaga fan would struggle to pin on Wainwright. Like his mother and father - folk nobility Kate McGarrigle and Loudon Wainwright III - Rufus has never been shy of documenting his personal triumphs and tribulations in song; and they've rarely been conventional.
One of his greatest recent personal joys was the birth of biological daughter Viva: who will be brought up by the triumvirate of Wainwright, fiance Jorn Weisbrodt and mum Lorca Cohen - daughter of Leonard.
Wainwright's ode to Viva and her unorthodox parentage, Montauk, is one of Out Of The Game's loveliest moments; a scampering, surprising vocal set to a swirling, twinkling synth backdrop.
Wainwright hasn't been this satisfied - or, to be frank, this stable - for some time. The death of mother Kate from cancer in January 2010 hit him seriously hard, her final months informing the moving if commercially-disinterested bleakness of last album Songs For Lulu.
It's a tricky subject to broach; one loaded with mercurial potential. But one, says Wainwright, that his US label Decca has treated with kid gloves.
"They've been pretty good with me," he comments. "On my last album, a lot of them were holding their breath: 'What the hell are we going to do with this thing?' We'd had such a traumatic period in the Wainwright-McGarrigle enclave.
"I'm very thankful and appreciative of them giving me that space - but it was understood that the next record had to be pop. That was intimated to me by my agent, by my label and by Barbara [Charone] to a certain degree: 'Okay, you've had your dress-up time with the feathers and the make-up. Now we need to be able to get to work.' It was very gently done."
Charone's name materialises a few times in our chat: Wainwright says the MBC PR co-founder championed him in the UK back when the knives were out - even, to some degree, amongst his own professional clique. (It may be no fluke that track four on Out Of The Game is simply entitled 'Barbara'.)
"When I started out in America I had this insane posse of record company people like Mo Ostin, Lenny Waronker and David Geffen," he recalls. "I hung out with them because there was nobody else on the label except me and George Michael.
"At that time, there was a brief period of serious cross-continental blindness. Initially in England, even some of the same people I still work with now were a little bit resentful towards me. They felt I'd been handed to them by the LA music monarchy, and that they had to work with me out of deference to these historical [business] figures. It wasn't easy. But then I think that they - and I'm talking about the product managers and the record label heads - began to appreciate me as an artist."
This led to what Wainwright calls a "long-lead" perspective of his career expectations from Universal in London. He has remained on the UK label ever since - bringing a stability for which he is very grateful, and at odds with his imprint-shuffling in the States. (He made records with the likes of Dreamworks, Geffen and Interscope over the Pond before signing with Decca.)
Which all reminds us that Wainwright can boast a rather rare position for a trend-averse singer/songwriter in the modern age: that of a true industry survivor.
He recorded his first album 14 years ago, and despite it costing near a reported $1 million, didn't release any singles from it. He squirms slightly as he recalls the "floor falling out" of major labels' patience with their investments - after which his bigwig US record company supporters "cut me loose, and put me back into the ocean".
So how come he has never become lost amongst all the unsigned plankton? Talent aside, what is it that has repeatedly drawn the market's cautious purse-holders to covet his signature?
"Being able to perform solo at a moment's notice has really helped," he says. "That's something I learned from my dad: he mostly does shows alone.
"When the buildings have crumbled and the street lights aren't working anymore, I can get up and play a song on the guitar. That is very much appreciated, especially here in the UK.
"Also, my first label could tell early on that I was able to ingratiate myself press-wise. I had a certain amount of knowledge, the ability to converse and I don't look so bad in a picture. It's quite simple: I give a great interview."
Lady Gaga and Mark Ronson might have a few words to say about that - but you won't hear any argument from us.