I don't know about anybody else, but when I read what purports to be nonfiction, I assume that it is not fiction. I know perfectly well that memory can be both deceiving and elusive. But I can take that into account if you make it clear that you are recounting things as you remember them. But if you tell me you have researched this matter and that, to the best of your ability, you are recounting things as they are, not simply as you remember them — and I later find out that you have in fact made up stuff, well, I am going to be angry, not at myself, but at an author who lied. There is really nothing subtle or difficult about any of this.