This has been on my mind for some time, and I'd actually previously written up something to post here, but I dropped it until the discussion on the following question:
Basically, it seems to be SF&F SE policy to close questions as a duplicate if they are anything alike, regardless of whether or not they are a duplicate, or if an answer on another question even touches on the answer to the new question, even if the actual questions are totally unrelated. @JasonBaker mentioned that this is official policy, though I was not able to find anything specific on Meta, then or now.
To be clear, I have nothing against marking questions that are actually duplicates as duplicates. But what I see over and over is marking any question, even if only tangentially related, as a duplicate of another if one answer even slightly maybe touches in passing information that might be an answer to a new question.
I don't see any benefits to this policy. And actually, to SO blog covers some of this topic pretty well.
...but this issue is a little different. We're expecting users who ask a question parse out potentially unrelated questions and scroll through answers possibly consisting of mostly unrelated content that may somewhere touch on the answer to their question, rather than receiving an answer that is tailored to, and directly addresses their question. Why? The upsides seem legion: searching for answers to questions is easier, users get direct answers to their distinct questions that touch on any subtleties rightfully missing from answers to other questions, and we can still mark questions as related if they contain potentially valuable information. I've found this to be especially egregious when those voting to close aren't intimately familiar with the source material.
What are the downsides to being less aggressive about marking questions as duplicates? Why don't we move forward to at least stop marking distinct questions as duplicate? (As opposed to the current policy where distinct questions with similar answers even if those answers are not the accepted answer can be marked duplicate.)