On Reaction we’ve carried some punchy stuff on the transition deal that the government and the EU announced earlier this week. Gerald Warner accused the government of surrender. The fishing industry has been betrayed, he and others charge. Stuart Wheeler argued that the deal is appalling and the UK just needs to get out ASAP with no transition.

I hear what they’re saying and share some of the frustration. It is particularly vexing how slow the Tories have been to explain what the transition is about, first calling it an implementation deal which it is not. However, in the circumstances – wouldn’t have started from here, and so on – I think it is a sensible deal that increases the chances of Brexit happening in a constructive and calm fashion, rather than it unfolding as chaos.

Here are five quick points in defence of the deal.

1) The UK government is not ready for Brexit, thanks to the way in which the politics has unfolded since June 2016. Preparations for “no deal” should have been started straight after the referendum with a dedicated cabinet minister based in the Cabinet Office and a giant graphic on the wall covering every task that needed fixing, freeing David Davis to focus only on the talks. That option was not chosen and decisions taken now must surely reflect the reality of the situation.

2) The EU is not ready for instant Brexit in March 2019 either. For a start, it needs the UK’s money until the end of its budget round. Transition provides money, and buys some time for preparation and negotiations.

3) It took the UK almost 15 years, from the first background talks and through the first application (rejected in 1961 by the French) to get into the old EEC in 1973. Since then, we have become interwoven with the EU, our laws and regulations embedded in a complex structure. That being the case, surely it was always going to take a few years to get out safely? Withdrawal and the formation of a future deal as a gradual process conducted over four years seems pretty reasonable in the circumstances.

4) The City and UK business – and some EU businesses – need reassurance and this way they get to make one transition (at the end of the transition at the start of 2021) rather than having to fall out of the EU next March with no deal and then adjust again to any subsequent free trade deal done later. This smooths the process, hopefully. It seems less likely to create panic.

5) The request for transition will, I suspect, turn out to be a classic piece of British compromise and pragmatism that works, but we’ll see. Article 50 is a process that was designed (by a pro-EU British official, funnily enough) to make it difficult to leave. Its design is rigid and deliberately unhelpful. Time is short.

Transition as an idea was an improvisation, first floated by Lord Bridges in the Lords last year as the “bridge” to Brexit. It was adopted by ministers and officials, quite properly. Of course there are compromises involved. Life is often like that.

The alternative was a mess next March.