On BBC1’s Sunday with Laura Kuenssberg the producers have taken to opening the programme with the two main guests sitting opposite each other. It is meant to be the politics show equivalent of a boxing weigh-in, when fighters go toe to toe and try to “trash talk” an opponent into losing their cool.

Thus far, no politician has been daft enough to do so, but the set-up is revealing in its own strange way. It is an opportunity for banter, for showing that someone can think on their feet, is at ease with themselves. So it was with David Cameron and Sir Keir Starmer - one man who had been Prime Minister and one who wanted to be.

Asked if he had any tips for Sir Keir, Cameron said: “Plenty. Get a plan.” Short, snappy, glib, the sort of thing you might expect from someone reckoned to have earned millions in the time between leaving Downing Street and being brought back as Foreign Secretary. (Kuenssberg suggested a wage packet of £10 million; Cameron said that was not true but declined to give a figure.) Attention then turned to Starmer. Any advice from Cameron that would be helpful? “Well,” said the Labour leader, “the 2010 experience when he went from opposition into government would be interesting to discuss.”

In contrast to Cameron’s answer this response was dull, clunky, and open to misinterpretation. (Cameron had to form a coalition government; was Starmer accepting he might have to do the same?). It was also very Starmer.

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No-one ever thought selling the Labour leader as a future PM was going to be easy, yet it has to happen if the party is to win the next election. Labour is ahead in the polls but is the electorate buying Starmer personally? In the words of another Sir, mebbes aye, mebbes naw.

Not being Blair is working for and against Starmer. Blair’s record as an election winner is still golden. He reminds voters a Labour PM is possible, even desirable. But he will be forever tarnished by Iraq, a clear case of mis-selling if ever there was one. Starmer should be keeping his distance, yet the signs are that he is becoming closer to the former PM, whether it is sharing a platform or aides making use of all that glossy research and advice available from the Tony Blair Institute for Global Change.

Who knows, Blair might even be tempted to pop up in the election campaign. It is the last thing any former PM should do, but once the old ham gets the smell of the greasepaint in his nostrils he may not be able to resist.

So far, Scotland is buying Starmer, or at least giving him a hearing, with the credit for that going to Anas Sarwar. The two seem to genuinely like each other, the win in Rutherglen sealing the deal. They are comfortable enough with the policy differences between them, for example on the two-child benefit cap that Sarwar says he would scrap. While Starmer’s U-turn sits badly with MSPs and other Labour members, for now the patch is holding.

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Otherwise, Starmer’s tendency to U-turn is increasingly working against him. He was at it again on Kuenssberg’s show when the interview turned to the UK-US air strikes in Yemen. When running for the party leadership, Starmer promised a law giving MPs a vote before the UK could take military action. Cue a clip of a younger Starmer saying so. Yet he had given his backing to the UK taking part in strikes against Houthi targets after being briefed by Downing Street last week. While others demanded parliament be recalled, he did not.

There was no inconsistency here, he insisted, with a vote being necessary if there was to be a “sustained” campaign - in other words, boots on the ground rather than planes in the air. This was not the only U-turn before lunchtime. Turns out that a 2020 pledge of his to stop the sale of arms to Saudi Arabia was now off the table. “We will review the situation,” he said, as if Saudi Arabia was in the habit of changing its ways.

Perhaps it is the lawyer in Starmer that wants to keep his options open and not commit to simple promises. But when he does this in interviews it comes across badly. Either he has not anticipated the question, or he’s a ditherer who cannot think on his feet. Between this and his reluctance to say anything on spending, he spends every interview on the defensive. It may be wiser and more honest to be this way, but it doesn’t inspire people to get behind him, and that is important, especially if it is a long campaign.

As for how he comes across in general, opinion remains mixed. He doesn’t need the charisma of pre-Iraq Blair. In many ways being a steady as he goes kind of chap works in his favour. The next election will be the bland fighting the bland, and the electorate is okay with that after all the “excitement” of Johnson and Truss. Starmer is best left to be himself. There have been attempts to repackage him but these are generally cringeworthy.

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As Kuenssberg reminded him yesterday, being leader of the opposition is often described as the worst job in British politics. “It is,” confirmed the Labour leader with uncustomary fervour. He is right. He is in the unenviable position of having plans but no power to put them into effect. He has to appear a safe pair of hands while not sending voters to sleep. And he has to do all this day after day until Rishi Sunak deems otherwise. Compared to some Labour leaders, Starmer has had a relatively easy ride with the media, and with the public. He knows that won’t last forever and the closer it comes to an election the more under pressure he will be. On this latest showing the selling of Sir Keir has some way to go yet.