Here is what members of the Cabinet said to me when I pointed them towards the statement made in the Sunday Telegraph by the Prime Minister that she is "determined to deliver Brexit and determined to deliver on time - on March 29, 2019".
"Farcical" said one.
"Total delusion" said another.
"Verifiably untrue" said a third.
It's not that they doubt Theresa May is working to take the UK out of the EU.
It's just they cannot see how it is remotely possible that departure can be achieved in the less-than eight weeks remaining before the official leaving day.
And unless she is explicitly saying that she is now working for the most chaotic no-deal Brexit imaginable, which they don't believe is yet official policy, then they just cannot conceive how March 29 is a realistic date - because there is massively too much legislation to pass through Parliament.
But to be frank, that is the least of their anxieties.
Far worse for most of them is that they are guessing at her real strategy, since they don't believe her official line - that she believes the EU will move far enough, or at all, on the widely loathed backstop to secure a majority for a Brexit deal from the votes of Tory MPs and Northern Ireland's 10 DUP MPs.
Presumably the scales will fall from Theresa May's and all our eyes this week, when talks between the UK and EU resume on Monday and she - her ministers think - goes to Brussels towards the end of the week.
Or perhaps not, since her colleagues frequently tell me that her capacity to describe the absence of agreement as progress may well be without equal in modern political history.
As it happens, some in the Cabinet think the EU will ultimately write a legally meaningful codicil to the Withdrawal Agreement, which would have the effect of reducing the risk of the UK being forced to remain in the backstop forever to an uninterestingly trivial one.
They are convinced that Angela Merkel has a soft spot for May and the UK, and will somehow persuade the French president and the rest to become emollient.
Truthfully I think that is unlikely, but even if it turns out to be correct, there would still be perhaps 20 European Research Group Brexiter ultras - or possibly more - among Tory MPs who would never be reconciled to a deal that does not include an explicitly reopened and reworked Withdrawal Agreement.
So even the Cabinet optimists don't think that May can move the EU enough to get her deal through.
What is required is for Labour MPs to be converted to her cause (which is what I've been arguing here for days).
So for some ministers there is method in what on the surface is May's fatuous exercise of asking the EU to remake the backstop - which is that it is a cover to convert Labour MPs (or so they hope - since she won't tell them and honestly they're not sure).
And to digress briefly, Sajid Javid's statement on Sunday on The Andrew Marr Show that alternative technological arrangements to the backstop "can be done" was described as "laughably absurd" by one of his close colleagues with knowledge of the latest thinking of HMRC and the Border Force.
So this will be a week which at best could - but probably won't - convert a few but not enough Tory Brexit sceptics to her cause.
More important will be whether progress is made by May in wooing Labour MPs - though there is ambiguity about whether she is hoping a caucus may be prepared to defy the Labour whip or (and ministers see this as a much longer shot) Corbyn and the entire Parliamentary Labour Party could be talked round.
Ministers know that converting enough Labour MPs almost certainly requires a commitment that the long-term relationship between the UK and the EU will be based on the customs union - which of course risks alienating more Brexiter Tory MPs, but could bring the DUP back as a supporter of the Brexit deal, since it would (as I've said many times) turn the backstop into a demonstrably short-term bridging arrangement.
But May's Cabinet hasn't the faintest idea whether the Prime Minister will ever compromise her red lines far enough to embrace customs-union membership as an explicit aim of policy.
Some ministers are crossing their fingers that the next time parliament is allowed a vote on backbenchers' Brexit-related amendments, on February 14, at least one enterprising centreground Tory will table a call for a customs-union destination for the UK.
"That would flush out whether the PM will ever opt for the only practical compromise," said one minister.
Were May to relent and go with a customs-union-based Brexit, the resignation of the secretary of state for international trade, Liam Fox, would not be far behind, of course, since he would no longer be able to negotiate free trade deals under customs-union rules.
But that would be trivial collateral damage, compared with the mass Cabinet resignations were Theresa May to abandon all hope of a deal and instead make it official policy to go for a no-deal Brexit.
Up to a third of the Cabinet would quit in those circumstances, including Chancellor, Justice Secretary, Business Secretary, Work and Pensions Secretary, and Minister for the Cabinet Office.
But all this is in the realm of probability and hypothesis.
The only certainty, among Cabinet ministers other than the most important one, is that March 29 is now only a reference point for setting the real date of departure, rather than the departure date itself.
And what a significant number of ministers tell me is that there will be mass government walkouts on or before February 14 - to take advantage of that next available date to vote to rule out a no-deal Brexit - unless before then the PM publicly announces an intention to negotiate with the EU a postponement of Brexit day of at least three months.
So the current few days matter, probably not in definitively determining what kind of Brexit, if any, will ultimately be the UK's destiny, but whether May very explicitly attempts to delay Brexit as the price of pre-empting and preventing so many ministers quitting that (again) her own tenure in Downing Street would be in jeopardy.