Should the site ever grow large enough, I predict you will experience large groups of people looking to game the system ala reddit's despicable /r/TheoryofReddit.
I read it and it was a good comment, but I think it's a mistake to assume that this can be sustained in the event that the site really does take off. Such a stable environment is possible in a small online community but less so in a larger one. I'm not suggesting you should penalize users for behavior they haven't yet engaged in but I do think it's important to be aware of the danger that there are always going to be people who derive enjoyment from gaming the mechanism of any website they join.
/r/TheoryofReddit isn't that bad. Sure, there are a few people just trying to game the system, but I love going there and seeing the interesting takes on how reddit functions. It really makes you understand the underlying culture of reddit from a numerical perspective rather than just the perspective of a user.
Wouldn't it be easy enough to lie about why you're downvoting and claim that original content is actually duplicated?
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