I recently seen some questions being retagged as "duplicate-question" by users who have privilege to do so. I personally fail to see how doing such makes it easier to find the duplicated questions unless the original question also get retagged so they are found in the same tag search. Or is this a suggestion to close the question? Could people tagging questions "duplicate-question" please answer why they are doing so, and why it makes sense doing so?
It's for closing the question, when we're all paying attention
My personal philosophical approach to this is:
If it’s band new I try to post the link and remove all content-related tags and replace them with ‘duplicated question’. I hope someone will close it and people will answer in the linked thread.
If both copies already have a really useful reply I cross-link them and leave the tags be.
If it’s old but has any useful answer I usually leave it be, even if someone noted that it’s a duplicate.
If it’s old and doesn’t have any useful answer, noone wants to find it; or if it is found anyway, you don’t want to have to click on it to find out that there’s nothing there but see it from the tag. So I remove all non-existent-content-related tags and only leave ‘duplicated question’.