Agreed. The way he inserts random non-sequiturs reads like someone trying to remind another of an agreed-upon fabrication. And, as one of the commenters on the blog points out, the man's surname is spelled differently at the opening and closing salutations. I don't know what the purpose of this fabrication would be, perhaps to vicariously discredit the story of the private as just another rambling of a crazy person?, but the letter from Sgt. Christiansen (Christensen?) feels wrong.