By Jove, Holmes, that was brilliant. Also that wiki entry answers my next question - what this Derschau did to make Fritz resent him, and for Seckendorff the Nephew to list him among people Fritz (so he assumes based on Manteuffel intel) still hates for his capture and imprisonment. Wiki says that Derschau was in charge of interrogating Crown Prince Fritz. Who by 1740 wasn‘t retaliating, however, since Derschau distinguishes himself in the First Silesian War and gets the Order Pour Le Mérite. And then he dies of indigestion.