The issue is people thinking leave means one thing. It's why we still get sub-intellect radio hosts and newspaper columnists yelling "just get on with it". The sad truth is the people championing Brexit and perhaps many of the people who voted for it, are too thick to actually know what it is. It's never been as simple as deciding to walk out of a room yet whenever anyone who supports Brexit speaks they refer to it in terms as if they genuinely think it's as straight forward as leaving a room, and that's gone from being comical at the beginning, annoying in the middle and is now bloody dangerous as we approach the end.
This is what "Brexit means Brexit" gets you. The nutters lapped that up because it gave them an excuse not to think. Who cares what type of trade deal we want or are likely to get, Brexit means Brexit, right? And if that doesn't work shout "Just get on with it" a few times.
The only positive is that the EU do want us to stay so they would be willing to extend/defer the Article 50 leaving date. Everything we know about what the EU wants, what they've said and what their likely neogitation strategy to be is keeping the UK practically in the EU. Because there will be an economic impact on them too if we crash out. The idea they'll get to March 29th and decide they'd happily take that hit because they're 'bored' of the process is every bit as ridiculous as the analysis that the hardline Brexit nutcases are pumping out.