That's simply not true and I'm not sure where you've got such information. MFN only applies to countries with which we do not have a trade agreement (or RTA in WTO terms). It's all on the WTO website if you want to read about it.
Step through what you've claimed and see if you can see the logical problem. Both Canada and the EU trade with much of the world on WTO terms. Both are members of the WTO and both have agreed to the principles and procedures which that membership requires. Yet they have both come to a trade agreement to trade at lower than MFN terms and neither have to trade with the rest of the world on those terms.
That's because the EU and Canada have a trade agreement (RTA) to do so.
See the above - the world is trending towards zero tariffs, the EU is remaining in a protectionist bubble.
I've spoken, personally, to people with enough control in their banks (admittedly not CEOs) to know the short, medium and long term planning inside-out. Not a single one of them is planning on moving more than a small number of jobs into the EU to brass plate their EU business.
What they say publicly is attempting to avoid that cost, but there is no way any of them will be moving from London - as much as anything because those who make the decisions don't want to.
Because it has to. The EU attempted to pass a law that ensured all Euro transactions were completed within the Eurozone and the ECJ struck it down.
Can I have some sauce with that please?
London's rise started well before the close integration of the EU. London was the world's financial capital before New York was and it swung back to London with the Big Bang and low regulation (something the EU has been continually trying to restrict).
London is also perfectly placed in terms of time zones, overlapping with all the major financial centres. Our legal system creates a very predictable and certain outcome for anyone who requires it, and Europe doesn't even come close to us in terms of protecting the rights of shareholders and creditors (from the World Bank here:
http://www.doingbusiness.org/rankings). There's no comparison in terms of education either - not if you're looking at top level economics (
http://www.shanghairanking.com/SubjectEcoBus2015.html). Europe also only has one Masters of Finance program to our four.
Mainly though, those making those decisions want to be somewhere everyone speaks English. They want their kids to stay in English schools and they don't want to have to commute halfway across Europe. They want to be able to walk across the street to have lunch with the head of their insurers or their audit partner and they want to live in the city they know and have arranged their lives around. London's place as a centre of finance didn't start with the EU, it started with British Empire and has been building on it for centuries. There's an infrastructure and an inertia that something as short-lived as the EU simply cannot budge in its short lifetime.
Nobody invests on uncertainty - that's just not how business works. Look at how investment stopped before the referendum, picked up again after and has now slowed as the deadline draws near.
I'm not surprised that manufacturers are moving to lower wage countries - that's how manufacturing works. Unless you have a unique product with no competition you continually engineer out costs. My business has an overseas arm where labour is cheaper - I'd expect that of most companies. If we want that kind of work (and I'm not convinced we do) then we need to set our stall out as a low wage, low regulation country.
Just because you don't comprehend an opinion doesn't make it nonsense. If economics was as simple as listening to what someone else tells you and agreeing with them why are we even having this discussion? Why didn't you just agree with me ages ago and save yourself the bother?