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That's not a good idear at all... For example, if i had some kind of grudge against somebody, I could just copy one of their original posts and paste it on my blog with a backdated timestamp, so it looks my blog article is older than the original post my victim made... Then i could just click the button => BAM autoban.
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Then copy somebody else's work and post it on my blog with a backdated timestamp... Then i could create a newbie account on bitcointalk over my VPN or tor, and get a senior member autobanned... Sure, maybe the ban wouldn't stick, but the member would still lose access to his/her account for a while untill the admin has time to look at his ban appeal and unban his account.

I'm not in favor of an automatic ban mechanism...
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