It is not. No-deal is probably the most demented policy put forward by mainstream British politicians in the modern era. To see how it would work in practice, this piece looks at what would happen on day one. Doing this for the whole economy would take countless pages of Stephen-King-style horror, so it's stripped down to one topic: food. This is the story of how our system for importing and exporting food implodes almost instantly.
Food is just one issue. Not a trivial issue, of course, but it is like this for *every* issue.