This is a quote from the book "The Gentleperson's Guide To Forum Spies" by Cryptome.org
...In this technique a number of unrelated posts are quietly prepositioned on the forum and allowed to 'age.' Each of these misdirectional forum postings can then be called upon at will to trigger a 'forum slide.' The second requirement is that several fake accounts exist, which can be called upon, to ensure that this technique is not exposed to the public. To trigger a 'forum slide' and 'flush' the critical post out of public view it is simply a matter of logging into each account both real and fake and then 'replying' to prepositined postings with a simple 1 or 2 line comment....
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