I haven't read any of the M*A*S*H books since I was a kid and probably wouldn't have noticed. But from I what I remember, I can see that that might be the case. I am capable of suspending annoyance somewhat when books/movies are accurate reflections of their time, which I suspect is true for M*A*S*H. (At least according to my mother, who was her high school's valedictorian in that time frame, but never managed to become the doctor she wanted to be...) But it can be jarring and disconcerting.
Of course, it can be disconcerting the other way too - when a historical fiction book gives agency to women or other minorities in a time when that was really unlikely to happen. But at least it's a nicer kind of disbelief to have to have
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