1. As catastrophic as @ShippersUnbound no deal preparations *middle scenario* suggest a cliff edge would be, they are not in themselves a reason for another referendum.
2. There are three other options available, all have downsides, but so does reversing Brexit without a change in public sentiment about what the EU is about.
3. A UK conscripted in the EU by its own inability to organise brexit will be a deeply divided and unhappy country. The Leave movement won't go away, any more than the complete failure of the 1916 rising caused Irish nationalism to go away.
4. The other options available are -
(A) Norway + CU
(B) Canada + Special Status for NI
(A) Norway + CU
(B) Canada + Special Status for NI
5. Remainers will point out they're inferior to remaining; leavers that they're inferior to leaving fully, but they have different ideas about what "inferior" is.
6. But the country needs a debate in which the tradeoff between the benefits of sovereignty and of political and economic effectiveness is discussed.
7. Will that happen? Probably not. I suspect it needs Brexit to be tried first. What is certain is that a further hurried referendum won't produce that debate.
8. It would be a turnout contest, polarise the country further and resolve England's crisis of identity, which is what Brexit is. ENDS.
