We keep getting told the Uk can get a deal like Canada, Turkey or other non-EU countries have, without FOM.
Those deals do not provide the same privileges as EU members:
They have quotas, restrictions and must obey EU regulations
e.g. After CETA, Ron Davidson, head of international trade for the Canadian Meat Council stated:
"We do not have what we would call commercially viable access to the European market".
The deal with Turkey abolished tariffs, but did not give free acess. This is what that means:
www.ft.com/content/b4458652-f42d-11e6-8758-6876151821a6
"On a recent Saturday at the Kapikule border crossing, about 30 minutes drive from the Turkish city of Edirne, a line of trucks 4km long stretched along the highway, inching along glacially towards the Bulgarian checkpoints.
"Today is a good day", said Ibrahim Kurtukcu, a 42-year trucker who had been waiting 14 hours.
"Last week the line was 7km long".
The record is 17km. It can take up to 30 hours to get through to the other side."
Of course, UK ports (and French ports) do not have the capacity, facilities, storage space or trained staff to handle customs processing of the vast amount of British exports & imports.
Building this additional capacity - where ? - would take several years and there are no signs that even the planning stage has started.