There is no substantial connection between the current EU trade talks and Dominic Cummings’ recent work.  The former special adviser was increasingly preoccupied with the Government’s “moonshot” plans for new Covid-19 tests.  His friends say that he was leading in building an entirely new system from scratch, because the NHS test and trace scheme has not delivered the results that Ministers had hoped for, particularly on tracing and self-isolation.

Instead, the main players on the Government side have been David Frost, the Prime Minister’s EU adviser, and Oliver Lewis, his Brexit adviser – and an old Cummings hand from the Vote Leave EU referendum campaign of 2016.

Nonetheless, the departure of Boris Johnson’s Chief Adviser complicates the calculation about what will follow when the talks conclude.

If there is a deal, the political context within the Conservative Parliamentary Party is likely to be be continuing confusion and suspicion about the Government’s so-called “reset”.

On the one hand, there was no love lost between many Tory MPs and Cummings, and most of them will have been glad to see him go.  On the other, the mass of bewildering rumour, briefing and speculation about the reset has had the effect, however temporarily, of turning the Prime Minister into a blank sheet of paper on which others are writing their hopes and fears.

This can only have the effect of making the European Research Group and other Brexiteering enthusiasts on the backbenches even more suspicious of any deal than they would have been already.  And Eurosceptics are a distrustful lot.

The new Centre for Brexit Policy argues that the Withdrawal Agreement is fatally flawed, and it follows from this point of view that any trade deal which flows from it is in the same condition.  Our sense is that pro-Brexit MPs haven’t united around this position, but the Centre’s luminaries include Iain Duncan Smith and Owen Paterson, so it will have a voice and influence among them.  Martin Howe is also involved and set out his view recently on this site.

And if there isn’t a deal, the Prime Minister will find himself without the adviser who, for all his recent distance from the present negotiation, was fundamental to the Government’s political strategy on Brexit before last year’s election.

The prorogation gambit might well not have happened without him.  It failed, because it was struck down by the Supreme Court, but also succeeded, because it helped to persuade voters that Johnson was serious about leaving.

The Prime Minister will be in a lonely place in the event of No Deal.  Most Party members will doubtless back him emphatically if it happens.  So will many Conservative MPs – though, we suspect, a smaller proportion.

At Ministerial and Cabinet level, the percentage is likely to be even smaller.  Michael Gove’s previous role at DEFRA, where he was focused on the potential Calais-related bottleneck, will have left him nervous of No Deal, as will his present experience at the Cabinet Office dealing with Covid-19 – and what is has shown up about the creakiness and dysfunctionality of much of the British state.  The Treasury and the Business department will also hope for agreement.

Then there is the Scottish dimension.  The Scottish Party needs Johnson to deliver on fish, but its leading lights also want a deal.

Yesterday, Frost tweeted that “we are working to get a deal, but the only one that’s possible is one that is compatible with our sovereignty and takes back control of our laws, our trade, and our waters. That has been our consistent position from the start and I will not be changing it.”

That use of the first person singular suggests a message to nervous pro-Brexit Tories: that Cummings’ departure hasn’t softened the negotiating position.

As for the talks themselves, we have always thought that a deal is more likely than not, and that seems to be where most business opinion too – doubtless on the intutive ground that if an agreement has been reached once with the EU on Brexit, then it can be reached twice.  And it is true that state aid, fishing and the so-called level playing field don’t have the raw political sensitivities of the Withdrawal Agreement-stage matter of the UK-Ireland border.

None the less, some of the most informed reporting at present suggests that the two sides of the negotiating table are “miles apart” on fishing, closer on state aid – and at loggerheads over regulatory and other alignment.

So: if No Deal happens, it will come as shock to much of institutional Britain, and Johnson will face problems within the Government, particularly at Cabinet level.

And if there is a deal, the path is uncertain.

On the UK side, legislation to implement the treaty in which it would be contained would need to pass through both Houses of Parliament before the end of the year.  In theory, Labour and the opposition parties ought to prefer any deal to No Deal.  Practice might be another matter.

On the EU side, a so-called “mixed” agreement could take several years to ratify – assuming that this happens in such circumstances.  The EU could provisionally apply a treaty but only after the European Parliament and Council have voted on it.

And finally: there is a draft treaty in the making – with a mass of blanks where issues are unresolved.  It apparently runs “to some 600 pages, including annexes”.  There’s a discontinuity between the scrutiny that such a text would need and the time available to probe it – with an unofficial deadline of the end of next week for talks to conclude.