So what is the UK's decision to be, deal or no-deal? A 10% tariff would presumably change the "industrial logic" 
When trade experts talk about market size being the key determinant of bargaining power in an FTA the future of Nissan and various other UK manufacturing sites is a classic example.
Putting this week's negotiations in context. Negotiators can agree technical detail and explore alternatives in tricky areas. But they can't change the political decisions. They can explore alternative level playing field provisions, but not remove them.
And fundamentally the EU will not change their position of requiring tough level playing field conditions in exchange for a deal. Because they don't want the UK offering vast amounts of state aid to allow manufacturers to take advantage of zero tariffs. So we have to choose...
Don't think Sadiq Khan has much agency with the UK government. Don't think they'll extend. But that likely means choosing between a problematic deal and no deal in September, both with likely long term effects. Their choice.
