We are now into the third year of the eve of Tory party conference tradition of Theresa May doing a non-interview with Andrew Marr, non-answering some questions and offering a range of non-apologies for the latest disaster everyone thinks is her fault. “Let’s be clear about this”, however, actually isn’t, so before we get on to that let’s start with the background.

Jeremy Corbyn really could not have made it any clearer last week that over the coming days, unless the Conservative Party starts doing an even vaguely convincing impression of an even vaguely competent party of government, he stands absolutely ready to be the least Conservative prime minister this country has ever had.

In the face of such a clear and present threat, it appears not only that the two big ideas on offer so far in Birmingham are a “Brexit Festival” and a bridge to Ireland, but that the party is willing to fight a civil war over them. And we’re not done yet – if you don’t like either of them, after a massive data breach on the official app, you can text, call or just turn up at the front door of any member of the cabinet and tell them exactly what you think.

Think of Tory Conference 2018 as a bucking bronco ride. Tory Conference 2018 has already stacked it with spectacular effect while not even especially close to the front of the queue.

If Theresa May knows her priority in coming days is to see off the first phase of Boris Johnson’s assault on her job, at least on that front things are going well. The only notable bit of his weekend’s onslaught of media interviews was ITV’s Robert Peston being reduced to breathless laughter either at how stupid or how nakedly disingenuous Johnson was being.

And, in his big interview with The Sunday Times, his big idea is a £15bn bridge between Scotland and Northern Ireland, to go with the bridge to France he promised in January.

By 10.30am on Sunday morning, his erstwhile ally David Davis had told Sky News his “policies are not serious” and the home secretary Sajid Javid had tweeted jokes about a bridge from Belfast to Birmingham.

In other good news for the PM, that so much of her interview with Andrew Marr was spent trying and failing to extract a meaningful apology for the Windrush scandal, they never got on to discussing her big idea, the “Brexit Festival”, which will apparently showcase to the world the most divisive event to occur in Britain since the Civil War, and which the vast majority of young people hate.

Ms May, if you want to know what a festival that only elderly Brexiteers will turn up for looks like, well you’ve come to Birmingham slightly late – Ukip’s conference was last week.

None of which is to say that events with Andrew Marr did not get off to an acceptable start. Asked, “Is Chequers dead?” she simply replied, “No”. It was the straightest answer she gave all morning, albeit probably the least true.

We heard again the familiar pitch that Chequers is the “only meaningful option on the table” – her table, that is, because just as she’s rejected all the EU’s proposals, they have rejected Chequers.

Yet may maintains that it “keeps the single market intact from the EU’s point of view”. The whole, economic, political and just utterly fundamental point of the single market is that it requires the free movement of goods, services, capital and labour. And here was Theresa May, yet again, carving out one aspect of it (goods), telling the EU everything’s fine and wondering what on earth the problem is.

Just as last week with Mr Marr, Jeremy Corbyn was taken on a painful walk through twists and turns of Labour’s antisemitism crisis and asked if he wanted to apologise, so Theresa May was played a clip of Sarah O’Conner, a Windrush-scandal victim denied basic services despite having lived in the UK since for 51 years. She died two weeks ago, aged 57.

The prime minister was again glad to apologise for the wrong people having got caught up in her “hostile environment” policy, but not for the policy itself.

Still, as the credits rolled for what felt like an eternity, Mr Marr and Ms May sat in the kind of silence that felt like it might shatter the screen, there was time to be grateful for small mercies.