I don't get the point that the article is trying to make. Of course banks won't trade at mid-market price. Of course there will be a buy/sell spread. Take a lo

I don't get the point that the article is trying to make. Of course banks won't trade at mid-market price. Of course there will be a buy/sell spread. Take a look at exchange rates for more exotic currencies than British Pound vs. Euro. The buy/sell spread can be huge, and often reflects actual risks in keeping around large amounts of cash in volatile currencies.