MPs have voted through a bill to mandate the executive to seek an extension to the Article 50 process – and have imposed an unexpected extra condition on themselves: to debate and vote on the withdrawal agreement for a fourth time, coupled with a series of further concessions and guarantees on workers’ rights, offered by Theresa May in her doomed final bid to get Labour MPs on board with her plan.

The amendment, tabled by Stephen Kinnock and backed by more than a dozen of his colleagues, passed thanks to legislative chicanery by the government, who deliberately neglected to provide tellers for the No side, which meant that it passed by default.

The amendment places no legal obligations on Parliament other than to hold a vote, but a series of theories about why the government acted as it did are doing the rounds. The first is that they hoped that it would cause Labour to abandon its support for the bill as a whole, as the Labour leadership also opposed the amendment. However, because Labour’s legal advice – and indeed the legal and constitutional advice of essentially every lawyer and constitutional expert on the planet as far as I can tell – is that the amendment means very little there was no real prospect of that, and indeed, even had it it been Labour would have been highly reluctant to be left holding the bag for a no-deal Brexit.

But the second and more important consequence is that because the vote passed by default, there is no division list. Even in defeat, the bill risked creating a far more dangerous blow to Boris Johnson than any effort to delay no deal – a positive majority for an alternative Brexit approach. Had 30 or so Labour MPs actually voted for the deal, the path to a plausible and negotiable deal other than that favoured by Johnson would have been clear.

I think it is highly unlikely that such a path exists – the concessions May negotiated made it even more unpalatable to Conservative MPs and there is no prospect of a Johnson government signing up to an agreement that ends up with a closer relationship with the European Union than the one envisaged by May.

But the significant development tonight is that we cannot say for sure that is the case – and that a real threat to Johnson’s strategy has been, at the least, delayed.