So Corbyn says that if they make him PM, he'll help stop Brexit and then

[Burney]

I know. I'm just wondering what their justification would be if it became clear that it's a straight choice between Corbyn stepping aside and No Deal.

They will argue that only Corbyn's policies can deal with the consequences of the iniquitous Tory No Deal Brexit, which will be blamed for All Bad Things in perpetuity.

[Monty92]

They will argue that only Corbyn's policies can deal with the consequences of the iniquitous Tory No Deal Brexit, which will be blamed for All Bad Things in perpetuity.

But I'm talking about the (entirely feasible) scenario in which Corbyn stepping aside for one of yer Benns or yer Coopers would be the only way to *avoid* No Deal.

What would be their justification then?

[Burney]

But I'm talking about the (entirely feasible) scenario in which Corbyn stepping aside for one of yer Benns or yer Coopers would be the only way to *avoid* No Deal.

What would be their justification then?

They wouldn't need a justification. They could quite simply state that Corbyn is Leader of the Opposition and elected leader of the Labour Party and that it therefore falls to him to form a Government and that none of his MPs has any mandate whatsoever to do so.