I ask because the decision to short the pound was a coordinated attack among many powerful financial institutions. There is a reason collusion in other economic areas is illegal, precisely because it allows a "mispricing" to occur compared to what would happen if their were arms-length, fair competition.
Again, I have no idea if this is a valid criticism of Soros' trade, but the part of the article about him convincing other investors to go along with trade reminded me in a way of the agreement of SV companies not to poach each other's talent, which HN loves to decry as illegal collusion to depress wages.