The key to a two-hour gig is to start big and end big, and then it doesn’t really matter what you do in the middle.

So respect really is due to the BBC who managed to top and tail its two-hour Question Time election special with both of the two realistic candidates to be our next prime minister defending themselves against allegations of racism.

Come on, don’t pretend you didn’t absolutely love it. It wouldn’t be a Corbyn/Johnson production without plenty of talk about antisemitism and Islamophobia, would it? They're the tracks that really stir the soul.

Corbyn was out of the blocks first in a curiously successful format which allowed the three main party leaders, plus Nicola Sturgeon, half an hour of questions each from a frankly terrifyingly well-informed audience.

And terror really is the right word.

This was an audience who was angry about the Daily Mirror being banned from Boris Johnson’s tour bus, angry about Lib Dem bar charts on election leaflets, angry about the precise date on which the parliamentary report into Russian interference should or shouldn’t have been published. Is it possible, just possible that a key cause of our current national misery is that people are just too interested in politics?

And they were angry, in the very first minute, about an old and rather awkward video of Jeremy Corbyn which can be found on YouTube, in which a Jewish Labour MP — Ruth Smeeth — is heckled and hounded out of the actual launch of the party’s investigation into antisemitism. And then, with Smeeth gone, Corbyn, in his infinite wisdom, goes to shoot the breeze with the man doing the heckling.

“Why did you do it? Why did you do it?” a very, very angry South African man demanded to know. Corbyn simply replied that nobody should suffer abuse. But he had no answer for his conduct after Smeeth's heckling. ​

He was hopelessly found out. So found out, perhaps, that not 10 minutes later, he actually committed what’s known in the trade as "news". He actually said something significant: that in the event of winning a general election, and having a referendum, he would not campaign for Leave or Remain, but would in fact remain neutral.

Obviously, it’s auto-parodic, this stuff. The actual prime minister of a country just sitting it out while it takes the most important decision it will make in decades. It’s also acutely depressing for anyone who, say, shares the values of the Labour Party.

But there is some bizarre logic to it. Going into an election committed to holding an EU referendum and then not saying how you’ll vote in it is daft, but it was also the Cameron game plan. Where Cameron went wrong, we now know, is in actually campaigning at all. Corbyn won’t make that same error. If you don’t have any opinions, how can you be wrong?

Genius.

As always, on these occasions — and this is perhaps the truest testament to how hopelessly banjaxed we are as a nation — the most eloquent, the most persuasive, the most likeable and the most serious candidate was obviously the one that 93 per cent of the population can’t vote for, isn’t even standing in the election, and is only in politics to break up the country.

But that’s enough about her already.

Jo Swinson will certainly have pause to wonder if she’s made a few wrong calls, given that the only thing that managed to unite a highly partisan audience was their mutual loathing of the Liberal Democrats.

That feeds back to our earlier issue, in its way. For most of the last four decades, the Liberal Democrats were sort of tolerated by the rest of the country as a kind of tedious, inoffensive uncle at a wedding.

Indeed, most of the country would have been shocked to learn that, within the Westminster bubble, utter undisguised loathing of the Lib Dems was the one thing that brought the main parties together.

Nowadays, everyone’s a politico, everyone’s an obsessive. And so the Lib Dems must pay the price. If this carefully selected audience can be said to be representative — and it certainly seemed like it was — the centrist Remainers hate the Lib Dems because revoking Article 50 is anti-democratic (it’s not, but no time for that now), and the Brexiteers hate them for even more obvious reasons. And the Remainy, Corbynista left hate them for, well, everything. At one point, Jo Swinson was told she couldn’t possibly be serious about stopping climate change because she’s also said that, if it came to it, she would fire a nuclear missile.

What a genius observation. How can you possibly want to save the planet if you would also nuke it? She really should have thought of that one. The Lib Dem policy on Trident should be not just to renew it, but to carbon-offset it. Ten billion trees for every one nuclear warhead.

All of which brings us tragically on to Boris Johnson, who shuffled out last, to deliver the same old drivel. When he tried to tell them about “getting Brexit done”, about “unleashing Britain’s potential”, they groaned. They know it’s garbage.

The age-old political strategy about repeating your mantra time and time and time again, hammering it home, is designed simply to make sure that anyone who’s only half-paying attention eventually hears it. But one does wonder, in this age of media saturation, of viral clips and constant access to news, whether a re-think is due.

Theresa May’s “strong and stable” ended up on the front of ironic birthday cards in novelty gift shops. Johnson is rapidly going the same way. Not least because a lot of his slogans are demonstrable lies.

When he was asked, with his first question, whether he believed it was important to tell the truth, and he said yes, the audience just laughed and groaned.

They groaned even louder when he mounted a feeble defence for his long decades of racist, misogynistic and homophobic newspaper columns, some written as long ago as, oooh, the summer before last.

He hasn’t got a leg to stand on, but it doesn’t matter.

He will, in all likelihood, win this election in a few weeks' time. A man who cannot go on television without being laughed at every time he claims he isn’t a liar.