Is upvoting duplicate questions really following the guidelines of the all mighty
The question shows research effort; it is useful and clear
I raise this question after recently receiving this comment on a duplicate question.
@FreshPrinceOfSO Then close-vote on that basis, please. At the same time, there's nothing wrong with up-voting a question that has already been asked. – Jonathan Sampson
I don't believe the question shows research effort because the OP would have discovered the duplicate questions. Further, I don't think it's useful being a duplicate. Given these two criteria, it seems like the question merits a downvote and a close.
In my opinion, upvoting the question just raises the question to be "valid," which I don't feel supports the principle of voting up.
Voting up is how the community indicates which questions and answers are most useful and appropriate.
... and it should be discouraged.