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I keep seeing this over and over and over in the review queue.
Yes, story-idents can have identical answers, but this doesn't make them identical questions. Each person asking remembers different details, and would have little luck looking through older questions to answer their own. If they remember A and C about the story, but the other question describes B and D, this is then not a duplicate question.
Sometimes this even happens when the two answers are not identical (a short story that becomes a television episode or a novel that becomes a movie). This is even more absurd in my opinion.
Furthermore, this is the best resource anywhere on the internet to ask for story identification (at least within the narrow bounds of the genres we support). When we get all antsy and start closing questions in this manner, we're not only upsetting new users, we're making this SE a little worse at one of the things that it really shines at.
We do sometimes close non-identical questions when the answer from one suffices to answer the other... but those are non-story-identification questions and this makes it different. One could be expected to find those answers from the previous if they did some modest research, and so it need not be rehashed in a case like that. But the person who asks for identification just may not remember enough details for that research to be possible. Nor can we feasibly edit the extra details into the original question... to do that to the extreme extent would require every detail of the novel or movie in question.
I contend that if we couldn't merge the details from both versions of the question without leading to absurd scenarios where we replicate the entire work inside the question then this means that they are not duplicate questions at all.
I would implore you all to have a light touch here, but since that just doesn't seem feasible, can we at least come up with some clear policy on the issue?