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I don't understand why we're not allowed to ask, "What have you tried?" in the comments section of a question. Can anyone explain this decision?
Probably because it's very easy to abuse that comment. If it's obvious that OP hasn't even tried anything, there's a downvote button(please see Shogs answer ).
Unfortunately people tend to mimic one another( I didn't even know that there were cases of multiple "What have you tried"'s in one post ) ...