Thanks for your quick response. I suspected it might be complex. How frustrating!
If you don’t mind, and at risk of making a nuisance of myself, I may ping you some specific, targeted questions relating to foreign transactions and trade. Hope that’s okay.
Fundamentally, I get (I think!) the notion that a floating exchange rate is an automatic stabiliser and that foreign trade today is not based on a commodity exchange, but a commodity and financial asset exchange. The seller (ultimately maybe the foreign central bank at the BOE) of course must desire to hold the foreign financial asset, assuming the right price.