With respect - that might have gone over the heads of some;-)I'm not sure that the outflow of capital will be that much. Money will be moved prior to a deal - it's all 1s and 0s now for the most part anyway.
An EU transaction tax would simply get companies to set up UK subsidiaries and borrow in the UK.
The only funds that can be directly affected are those that cover Euro clearing - and stopping that happening in the UK could result in a full on US trade war with the EU as it would also stop the US from doing some Euro clearing in New York.
Dublin is poised to take over from London as a global financial centre don't you know....