The problem with assessing the intentions of a serial liar is that disbelief becomes second nature. So when Boris Johnson stated his Brexit plans in interviews last week and over the weekend it was largely overlooked. The media and public preferred to focus Johnson’s absurd claim that he enjoys arts and crafts of the vehicular variety. Less a dead cat than a dead kitten.

What makes Johnson’s intentions even harder to assess is his absence of principles. He belongs to a vanishingly small group of Britons who believe in neither leave nor remain. It is not that he has changed his mind but that he has never much cared either way. For Johnson, Brexit was a passing bandwagon to the premiership, and he was prepared to climb aboard. It is testament to his political skill that he has hoodwinked the Brexit zealots into believing he is their man.

So could he be Johnson the pretender, the man who seized the Brexit crown only to betray those who handed it to him?

Johnson claimed that his “plan A” was to leave “with a standstill between the UK and the EU so we keep going with the existing arrangements until such time as we have completed our free trade agreement and we use that period to solve the questions of the Northern Irish border”. Rather than pausing the process inside the EU, it seems that Johnson might propose to park Britain just the other side of the line. 31 October would be a symbolic exit, legally out but practically in – Brexit in name only. It would be a dropkick of the can down the road.

Can Johnson really believe it is possible to hoodwink the nation with a wheeze that leaves us in the EU but with no say?

Such a plan could perhaps be described as the “backstop triple-plus” – that is, the customs union plus the single market, free movement and the full financial contribution. It would take the original 21-month transition negotiated by Theresa May and reformulate it to be “as short as possible, as long as necessary”. Doubtless the political declaration would commit to a Canada-style free trade agreement, a mutually agreed target end date for the negotiations, and empty promises to explore alternative arrangements for the Irish border. Is this what is giving Johnson “supreme confidence” that we will be out of the EU “do or die”?

It could be a superficially attractive option, which might appear capable of achieving a majority in parliament. As it wouldn’t really mean leaving, it would surely meet Labour’s “six tests”. It would unite Labour MPs from strongly Brexit-supporting constituencies, such as Lisa Nandy, with those who have advocated a Norway-style agreement, such as Stephen Kinnock. Johnson may calculate that it would deliver enough Labour votes to cancel out the irreducible core of European Research Group (ERG) opponents. The EU itself would be delighted: no impediments to the single market, the weight of the UK economy in trade negotiations, and our sizeable financial contribution with none of the aggravation caused by British Europhobes. Crudely, the UK would effectively remain in the club, albeit with no say, and Nigel Farage would be kicked out of the European parliament to boot.

But it is also a plan that is doomed to failure. If such a proposal were to be made, it would come unstuck in precisely the same way that May’s deal died on the backstop. The EU simply does not believe that alternative arrangements are possible for the Irish border. So the EU will refuse to commit to a legally binding end date for such a transition period. Johnson is badly miscalculating if he thinks the EU will abandon Ireland for the sake of a deal with the UK. Moreover, given how advantageous this arrangement would be to other EU member states, there would be virtually no incentive for negotiations on the future partnership to ever reach a conclusion.

It would be quite the comeuppance for leave campaigners. After decades of poisoning Britain’s relations with our neighbours and three years of squabbling, the only Brexit they could make work would be one where we never really leave but give up control rather than take it back. Stubbornness would be its animating purpose; the Brexit project would have defeated itself. Shrewd Brexiters would know the clock will be ticking until the UK goes from such a standstill transition back to full membership, only with a worse deal than today, losing both the rebate and the opt-outs we currently enjoy.

As a result, it would not face the 34 Tory opponents from May’s third attempt to pass the withdrawal agreement but more like the 75 who voted against it at the second attempt. Even if they believed that we would eventually arrive at a free trade agreement, the typical negotiation length is five to seven years, meaning as much as an additional £80bn in financial contributions with no say over how they are spent, the continuation of free movement (good for the country but detested by many Brexiters) and the entirety of EU regulation. So much for the promise of “taking back control of our laws, borders and money”.

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What’s more, if this is his strategy, Johnson is also badly misreading the mood of the Labour party. Sentiment is drifting away from a second referendum and towards revoking article 50 by a parliamentary vote. But more than that, this sort of plan would face fierce hostility from Jeremy Corbyn himself. Corbyn’s long-held Euroscepticism is firmly in the Bennite tradition: opposed to the EU on grounds of democracy and accountability. Labour’s six tests for Brexit would be replaced by Tony Benn’s five questions for the powerful. A solution that leaves Britain effectively in the EU but with no say runs entirely counter to his principles. If there was any plan that could provoke Corbyn from acquiescence to Brexit into outright opposition, this would be it.

Even if it were to pass parliament, it would provoke an immediate general election. The government has a working majority of just three, and if Johnson were to deceive the ERG in this way, they would surely prevent him from being able to govern. It would provide the Brexit party with the perfect narrative of betrayal: leavers would say “we never left”, and remainers would ask “what was the point?” Both would be right. Can Johnson really believe it is possible to hoodwink the nation with a wheeze that leaves us in the EU but with no say? With the right split between the Tories and the Brexit party, it is hard to see the path to a general election victory in November. For that reason, the most likely outcome continues to be an October election prior to a no-deal exit, where Johnson calculates that he will have five clear years to clean up the mess and turn things around. And gaining and retaining power for himself is the only principle to which Johnson has ever shown any fidelity.

• Tom Kibasi is director of the Institute for Public Policy Research and chair of the IPPR Commission on Economic Justice. He writes in a personal capacity