Other way round: the single market is extremely critical to the UK econonmy, as we've been seeing.

What have we been seeing? Lower pound is probably a major advantage to working class people.

We have such a high pound because we are a country driven by financial industry, people keep their wealth in pounds because of this. Ultimately it screws over other industries resulting in the south/north divide.

I've got a lot of sympathy for this argument, but without wage inflation coming as well there's going to be a short-term nasty squeeze as food and fuel jump 20%.

We saw this play out in Greece. The situation there was far worse, both at government and private level, but there still wasn't enough support for jumping out back to the Drachma and devaluting. And meanwhile the shortage of hard currency caused medical shortages.

The UK economy was/is doing fine? Not sure you read up on all the facts.