In its first seven years on air, Alan Jones didn't once appear on Q&A. In the last 16 months he has fronted no less than four times, including on Monday night - when he continued what has quickly become a tradition: this is where Alan comes to make good with his traditional enemies, and if possible to make a bit of mischief.

In the main, that mischief involves gently taunting his critics with evidence that he is not the one-dimensional right-winger of conventional wisdom, while also giving the present incarnation of Malcolm Turnbull a cheeky something to think about should the opportunity presents itself. And in the final days of this centuries-long election campaign, Jones was on hand on Monday night to raise questions about the one issue that has the Prime Minister tied in so many knots he looks like he misheard the instructions at a yoga class.

On the matter of his government's marriage equality plebiscite, the PM may eventually find a way to remove his foot from his ear and distinguish his elbow from whatever body part he currently has it confused with - but in the meantime, confusion reigns. As currently conceived, it is a contortion of democracy - the result of which no government MP will actually be obliged to recognise - and as Alan Jones was keen to note last night, it comes laden with worry at what it might unleash.

Jones didn't have to go there - in fact, the question at hand was a general one about young people and their disillusionment. Tony Jones had presented for discussion a tweet from a young Briton, post-Brexit: "I'm so angry, a generation given everything, free education, golden pension, social mobility, have voted to strip my generation's future?"

Jones: "I don't think that's the case but I can understand the sentiment … If I thought you were talking about marriage equality, if we were to step on what sometimes is controversial territory, and it hasn't come up tonight, but let me nail my colours to the mast - I'm certainly opposed to a plebiscite on this issue.

"And I think that when Bill Shorten made his observations about that and he argued a plebiscite was homophobic, that wasn't what he was saying. I think he was saying that there must be ways we can avoid the kind of exchanges that would occur if a plebiscite took place."

Jones then reminded viewers of the very recent history: "Malcolm Turnbull was in favour of a vote of the parliament and indeed he represented that view to me when he was the minister for whatever it was, NBN or something, before he became prime minister."

The background to that delightful "minister for whatever it was" sledge? Last year, Jones revealed that after the Abbott government adopted the plebiscite as its official we-have-to-do-something policy on marriage equality, then-minister Turnbull had called him and asked him to intervene. "This is ridiculous Alan, this plebiscite stuff," Jones quoted Turnbull as saying at the time.

Though the broadcaster agreed, he didn't intervene, but needless to say he hasn't forgotten.

"I think it would be very unfortunate if we went down a track where we have spent a whole heap of money and had people throwing insults at each other from both sides of the equation."

Tony Jones inquired: "Is the Brexit vote a bit of a warning there? I'm wondering if you can draw some reasons why you should be wary of a plebiscite?"

Alan Jones: "I think David Cameron called the [Brexit] referendum because he thought he would win it easily. That was the point. It was an error of judgement. I think here you do have to try to avoid on major issues such as that the kind of divisiveness we saw over there. One final point, there are 23 million people in Australia. They can't all sit in the federal parliament. We select 150 to sit in the House of Representatives to represent those 22 million people on critical issues such as this. I think we should do what Malcolm Turnbull originally said we should do, let the parliament decide."

Tony Jones: "Briefly, it worries you?"

Alan Jones: "It certainly worries me. I think that a lot of the young people are worried. I get a stack of correspondence about this. They're concerned about the direction this could take us and I think we can avoid, we can do without all of that."

It is not the first time the 2GB broadcaster has come out against the the plebiscite, but it's the first time the nation has heard him do it on such a big stage - and at such a big moment, in the dying days of an election campaign in which it is the one question guaranteed to inspire a prime ministerial frown. Cue more frowns today, as the Jones testimony puts the broadcaster in the unusual position of disagreeing with not one, not two, but three Liberal prime ministers -  Messrs Howard, Abbott and Turnbull all on the other side of the fence.

That doesn't happen often with Alan Jones, and it is Q&A that brings out the contrarian in him like few other platforms. And in this election week edition - with the Coalition's Mathias Cormann and Labor's Tanya Plibersek doing predictable battle over budgets and other campaign battle lines - Jones was, once again, the surprise packet who sent viewers away thinking they hadn't quite heard it all before.