"UK will adapt if barred from EU market"

No it will not. 

For all intents and purposes the only reality the UK has to offer as a viable economic "contribution" is the financial sector/the London Stock Exchange which dominates Europe and much of the world (including the United States and Canada)

Should the EU cut off access of the LSE to Europe (and they will) the Germans, French, Italians and Dutch will be more than happy to fill the void.

So long "mates", it was nice knowing you, now go back to your Queen, warm beer, bad (actually atrocious) food and substandard living standard. 

Too bad, you had "promise " there for a while.....................

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