This is a quote from the book "The Gentleperson's Guide To Forum Spies" by Cryptome.org
...vanish once the topic is no longer of general concern. They were likely directed or elected to be there for a reason, and vanish with the reason.

4) Teamwork. They tend to operate i
n self-congratulatory and complementary packs or teams. Of course, this can happen naturally in any public forum, but there will likely be an ongoing pattern of frequent exchanges of this sort w here professionals are involved. Sometimes one of the players will infiltrate the opponent camp to become a source for straw man or other tactics designed to dilute opponent presentation strengt...
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