“Mr Speaker, today marks 400 years since the sailing of the Mayflower,” the prime minister announced as he stood up in the House of Commons. The Pilgrim Fathers sailed during the reign of James I, a vain man with a complicated sex life who tried to rule without parliament and persecuted his opponents. When they reached America’s shores, many died from a strange disease. Plus ca change, and all that.

Johnson seemed perky, bullish even. It didn’t last. In recent weeks, PMQs has been dominated by Keir Starmer asking questions about virus testing. Johnson has tended to respond by accusing the Labour leader of talking down the system, seeming to imply that every tricky question he faces comes at the cost of 10,000 samples left untested, as demoralised scientists stare listlessly at copies of Hansard.

This week, Starmer had become a worked example of the testing problem, stuck at home self-isolating because one of his children had Covid symptoms. His place was taken by his deputy, Angela Rayner, who asked the prime minister if he knew the average hourly wage of a care worker.

It was a neat little jab of an unfair question, asking for a level of detail that few people would hope to have at their fingertips, but that didn’t explain how completely flummoxed Johnson seemed to be as he rose to reply. “Er well Mr, Mr Speaker I er congratulate er the er good honourable, right honourable, the honourable lady on her elevation,” he gabbled, as Rayner laughed at his confusion.

Johnson has on occasion been accused of having a “woman problem”. Stop sniggering. It’s argued that he doesn’t have enough women around him. Really, stop it. It’s certainly true that he had no idea how to behave towards Rayner. He didn’t want to patronise or hector her, and any attempt at caricature could backfire. The Tories are determined to paint Starmer as an aloof Islington lawyer. This sort of thing is unlikely to work on Rayner, a Mancunian who left school at 16 before becoming a care worker herself.

The safest course, which Johnson eventually landed at, was to play it soberly. That didn’t mean he actually answered her questions. But he swerved them straight, as it were.

Rayner wanted to know why so many people weren’t able to get Covid tests. Johnson replied that many people were, and that he wanted many more to. It’s quite hard to keep track of the prime minister’s testing pledges. Last week he was talking about Operation Moon Shot: millions of tests a day by Christmas. This time it was a slightly more modest promise – Operation Low Earth Orbit? – of 500,000 tests a day by the end of October.

Rayner was unimpressed. “Time and time again he makes promises and then breaks those promises,” she said.

Johnson’s promises should be understood as coming from a man who can’t bear to disappoint

The prime minister’s troubles with women didn’t get any easier as the day went on. In the afternoon, he faced the Liaison Committee, where Labour’s Catherine McKinnell made him squirm by the cunning manoeuvre of asking him why he hadn’t done some thing he recently promised a member of the public he would do. Johnson looked a mixture of baffled and worried, struggling to remember what he might have promised to who. These are deep waters for the current prime minister – people he might have met, things he might have said, promises he may have made. That’s a lot to remember and govern a country too. “A man needs time to think. Space, he needs space too. Yes, a Moon Shot! I need that. No, wait, what? Where am I? Oh yes, the Liaison committee, Bernard, oh dear”.

On the hearing dragged for poor Boris. The prime minister accused Mel Stride of being “slightly incoherent”, though it’s possible Johnson thinks of that as a compliment.

The committee wanted more detail about Moon Shot and got a perfect example of the way the prime minister’s promises seem to accelerate as he makes them. They begin slowly: “We are a long way off, I’m afraid.” Then they start to move down the runway: “Or, still some way off.” And then, seconds later, they are airborne: “The science is almost there”.

Johnson’s promises, though, should be understood as coming from a man who can’t bear to disappoint. It helps to think of him as a deadbeat dad (it’s a stretch, I know, but work with me), trying to compensate for a forgotten birthday by promising a trip to DisneyWorld. Operation Moon Shot should be taken less as an indicator of anything that’s going to happen by Christmas and more as a signal of the kind of thing he’d like to be able to give you. If only he weren’t currently living in his car.