“The British establishment do not have a great track record when it comes to the great questions of their era … Time after time the elite have got it wrong”.

When David Davis said this during the referendum campaign he had the luxury of being a political outsider, on the backbenches. It was a trick deployed by all the prominent Brexiteers: discredit the case for staying in the EU by manipulating the public’s distrust of politicians, and undermine the credibility of experts by branding anyone pro-European as “elitist”.

Now that Davis sits in the cabinet as the Brexit secretary – and, as surely even he would now have to agree, a member of the elite – it is only right that we consider how right or wrong he has been in his predictions about how the negotiations would unfold. Fortunately, the speech he gave during the referendum campaign, and his interviews and articles immediately afterwards, offered a series of predictions and promises against which his own progress can be judged.

First up, Davis said the Government should “take a little time before triggering Article 50” because “the negotiating strategy has to be properly designed, and there is some serious consultation to be done first.”

Quite right too. But it simply did not happen. Article 50 was triggered on the basis of an unachievable wish list. There was no negotiating strategy, and there still isn’t. As Davis conceded in March, the “no deal is better than a bad deal” mantra is not underpinned by an economic impact assessment – in fact he told the Brexit select committee that there won’t be one until next year. And consultations have only recently been launched (and will not conclude for many months) on fundamental issues including the impact of immigration on the UK economy and how a new customs regime might work.

Nonetheless, Davis had a plan for getting a quick win on the board. “The first calling point of the UK’s negotiator”, he argued in May 2016, “will not be Brussels, it will be Berlin, to strike the deal: absolute access for German cars and industrial goods, in exchange for a sensible deal on everything else.”

Needless to say, this hasn’t happened either, for several reasons. Firstly, because as was clear would be the case during the referendum, Angela Merkel is fully focused on the German election. Second, because Davis and Theresa May have singularly failed to build alliances, to the extent that the Prime Minister is said to have a “basically non-existent”relationship with Merkel.

But third, and most crucially, because individual member states can’t negotiate bilateral trade deals. Seemingly unaware of this fact, Davis went on to confidently predict that: “Similar deals would be reached with other key EU nations,” citing France, Italy and Poland as apparently easy wins.

The delusory predictions kept on coming. Along with the other Brexiteers, Davis consistently argued that the negotiations on both the terms of Britain’s exit from the EU and a new free trade agreement would be concluded within the Article 50 timeframe. “At the end of two years, we will have our deals,” As recently as 14 May he said he would have “the row of the summer” with Michel Barnier to ensure Britain could negotiate both deals alongside one another. Just weeks later he caved in, and today it looks as though talks on a future trade agreement (which will in reality take at least five years to negotiate) may now not begin until Christmas.

But we shouldn’t fear the impact of leaving the Single Market and the Customs Union, Davis told us last summer, because by autumn 2018 we will have negotiated a free trade area “ten times the size” of the EU. We were told that on 9 September 2016 the Government would launch “a large round of global trade deals” and that “the negotiation phase of most of them [would] be concluded within between 12 and 24 months.”

Disregarding the fact that Britain is prohibited from negotiating free trade agreements whilst it is a member of the Customs Union, he went on: “So within two years, before the negotiation with the EU is likely to be complete, and therefore before anything material has changed, we can negotiate a free trade area massively larger than the EU."

This was either staggeringly deceitful or alarmingly stupid. The reality of course, is that, as Davis and Liam Fox approach 9 September, the halfway point for this absurd commitment to be met, trade negotiations have begun with a grand total of zero countries. This will remain the case until we leave the Customs Union, meaning damage will be done to the economy long-before any new deals materialise.

And it is in fact worse than that. The 53 preferential trade deals we enjoy with the EU – which Davis confidently assured us last year “would stay in place until either side wanted to renegotiate” – do in fact require negotiation, and this has barely begun. The Department for International Trade is deeply unprepared and ill-equipped for the task ahead.

To this long list of deceptions by the Brexit secretary we can also now add a raft of broken promises made by the leave campaign, of which Davis was a part. The end of budget payments to the EU. An end to red tape for businesses. Immigration down to the tens of thousands. £350m a week extra for the NHS. An end to any influence of the European Court of Justice in the UK.

As one by one these totemic promises continue to collapse, along with the confident predictions of the Brexiteers, Davis seems to be doing a good job of proving his own point: that “the elite” really can get things spectacularly wrong.

Francis Grove-White is deputy director of Open Britain.