Okay, I just removed the reference to the last letter, which I had only put in in the first place to be historically accurate, not realizing that I was actually introducing an inaccuracy! Of course, I didn't realize at the time just how much it wasn't a letter from Katte. I knew it wasn't very comforting, but I hadn't realized it was written as if from FW, and I didn't realize it wasn't even in Katte's handwriting. I can see why Fritz was willing to get rid of it (it really works best as a missive to Grumbkow and FW, indicating that they should be nice to extremely reformed Fritz) so soon, while he clung to the coat (assuming Wilhelmine, our only source, is correct about that).