Character mistake: As Stauffen parts company with Col. Hogan at the road checkpoint, he salutes Hogan. While that is understandable under the circumstances - after all Hogan just saved his life, it would also be highly suspicious. Both Schultz and Stauffen's adjutant were watching them, so it can't be said they did it surreptitiously either. After all, Stauffen is a German general whereas Hogan is an allied prisoner officer of inferior rank. For an officer of higher rank to initiate the salute is a demonstration of great respect and/or thanks, which, as far as anyone besides Stauffen and Hogan knew, was not warranted in this situation.
Other mistake: When the General arrives at Camp 13 and is greeted by Klink, he notices Hogan and ask Klink who he is. Klink only says he's the Senior POW, the General sends his Aide to get Hogan. The Aide addresses Hogan by name, but Klink never said Hogan's name. (00:07:40)
Answer: Nimrod's actual identity was never revealed in the series. It was only known that he was a British intelligence agent. Nimrod was not Colonel Klink. Hogan had only implied it was him as a ruse to get Klink returned as camp commandant, not wanting him replaced by someone more competent who would impede the Heroes war activities. The term "nimrod" is also slang for a nerdy, doofus type of person, though it's unclear why that was his code name.
raywest ★
"Nimrod" is originally a king and hero mentioned in the Tanach and taken into the Bible and the Koran. His name is often used in the sense of "stalker," "hunter," and sometimes figuratively as "womanizer" as in "hunter of women." I've never seen it used to denote a nerdy person, and although I cannot disprove that connotation, I think given his role, the traditional meaning is more likely the intended one.
Doc ★
It's widespread enough that Wikipedia has an entire section on it: https://en.wikipedia.org/wiki/Nimrod#In_popular_culture