Given the propensity of thought-to-be-lost Morecambe and Wise episodes to turn up decades later in west African cinema store cupboards, we must advise the parliamentary archivists immediately to incinerate all recorded footage of the House of Commons between 12.41 and 13.53 on the afternoon of Wednesday 9 January 2019, and promptly blast the ashes deep into outer space.

Actually, perhaps that’s too risky. Should even an entirely benign life force chance upon the cold embers of what might yet go down as a signature event in Brexit: The Greatest S**tshow On Earth, it is liable to do the decent thing and guide its death beam directly over Westminster, like a kindly rural vicar reversing his Volvo over a maimed beagle.

The details of what occurred directly after the first prime minister’s questions after the Christmas break are far too tedious to inflict on anyone who considers themselves normal, but the scenes were as wild as anything that has happened in the House of Commons since, erm, the last Prime Minister’s Questions, now known as Stupid-Womangate.

In short: because last month, the prime minister cancelled the last “meaningful vote” on her Brexit deal, three days into the five-day debate on it, on Wednesday lunchtime, the government had to start the five-day debate again.

Now (deep breath) to have a debate and a vote in the House of Commons, there first has to be a motion to introduce it. It is a short, tedious administrative procedure. These motions are not meant to be amended. And yet, on Wednesday morning, it emerged that speaker John Bercow had, entirely without precedent, accepted an amendment to what is meant to be an unamendable motion.

The amendment, by Remainer Tory MP Dominic Grieve, would force the government, when it inevitably loses its vote next week, to come back to the Commons with a new plan of action within just three days, not 21 days.

In practical terms, it changes almost nothing, other than to limit Theresa May’s capacity to run the clock down, and ultimately force the Commons to either accept her deal or be responsible for the calamity of a no-deal scenario.

But the Brexiteers have never been more angry. As far as they were concerned, it was a clear act of partiality by a speaker who makes no secret of the fact he voted Remain, and, well, is Remain. It was an act of constitutional sabotage, and at the end of prime minister’s questions, they lined up one after the other to tell him so.

Bercow is used to such scenes, though none quite as unedifying as these, and is not afraid to fight his corner, but even he could not hope to uphold the weakness of his position, and he spectacularly failed to do so.

High on his green leather throne, the speaker is meant to be the Commons’ referee, and yet here he was, floundering like, well, like some politician, being hopelessly exposed and utterly failing to cover it up.

What had emerged earlier in the morning is that, when Dominic Grieve had first sought to make his amendment, Bercow had been advised by his clerks that he should not accept it, but he chose to anyway. When Andrea Leadsom asked him to publish the advice he had received and Bercow, naturally, refused, the house went wild.

Police separate clashing Brexit protesters outside Parliament Show all 11 1 /11 Police separate clashing Brexit protesters outside Parliament Police separate clashing Brexit protesters outside Parliament Anti-Brexit protester Steve Bray (left) and a pro-Brexit protester argue as they demonstrate outside the Houses of Parliament Getty Images Police separate clashing Brexit protesters outside Parliament A pro-Brexit protester argues Getty Images Police separate clashing Brexit protesters outside Parliament Police surround the pro-Brexit protester after he confronted Steve Bray, a pro-European protester Getty Images Police separate clashing Brexit protesters outside Parliament A leave supporter is spoken to by a police officer as he argues with a remain supporter, Steve Bray, outside Parliament PA Police separate clashing Brexit protesters outside Parliament MPs in Parliament are to vote on Theresa May's Brexit deal next week after her December vote was called off in the face of a major defeat Getty Images Police separate clashing Brexit protesters outside Parliament A leave supporter is spoken to by a police officer PA Police separate clashing Brexit protesters outside Parliament Police look on as anti-Brexit protesters demonstrate outside the Houses of Parliament. Getty Images Police separate clashing Brexit protesters outside Parliament Police hold back a leave supporter PA Police separate clashing Brexit protesters outside Parliament A police officer speaks with anti-Brexit protester Steve Bray Getty Images Police separate clashing Brexit protesters outside Parliament Police surround a pro-Brexit protester after he confronted a pro-European protester Getty Images Police separate clashing Brexit protesters outside Parliament Conservative MP David Davies, wearing a gopro camera, speaks to anti-Brexit protester Steve Bray Getty Images

“The answer is that I have discussed the matter with the Clerk of the House,” Bercow said. “The clerk offered me advice, and we talked about the situation that faces the house today. At the end of our discussion, when I had concluded as I did, he undertook to advise me further in the treatment of this matter – that seems to me to be entirely proper. That is the situation, and I think that is what colleagues would expect.”

It was an answer of equal parts Michael Howard and Brian Clough. Bercow refused to admit he had overruled his clerk, as Howard once refused to admit the same to Jeremy Paxman when asked the same question 14 times. But he did boast that the two of them had eventually come to agree that he was right, as the football manager Clough notoriously did in a post-match interview even longer ago.

I lost count of the number of times he was hopelessly skewered, by Leadsom, by Jacob Rees-Mogg, by Iain Duncan Smith, and by many others, to whom he could only say, “I will reflect on that.” To hear more promises to “get back to you on that later” in a short space of time, you would have to rewatch the footage of Mark Zuckerberg non-testifying before a US congressional committee last year.

On at least 10 occasions, Bercow, mysteriously talking about his job and himself in the third person, said he was “doing his job to the best of his ability”. Asked why he was so clearly breaking with precedent, he said, “If we were guided only by precedent, manifestly nothing in our procedures would ever change.”

It was, in short, a foul spectacle. And it should be repeated that Bercow only remains in his post because certain Labour MPs, most notably Margaret Beckett, were at least brave enough to admit last year that they were happy to overlook serious bullying allegations against him because they consider him an ally on Brexit, and they want him in post for scenes just like this.

The amendment passed in the end, 297 to 308. And the five-day debate on the meaningful vote is now underway. It was cancelled before Christmas because Theresa May knew she would lose it, and vowed to go to Brussels to get some concessions on the notorious “Irish backstop” that might give it some chance of passing. A month later, no concessions of any kind have been received, but the debate has started again anyway.