In the interest of the Biblical Hermeneutics community, I believe this question deserves a "fair" hearing.
Trollism and the Art of Trolling
"Troll"as the source quoted in the comment by the OP, is a subjective term, but it generally means 'A person with some sort of grievance or agenda who is merely looking for an audience to vent his/her particular rant/thesis upon.'The 'cultural image' of a Troll is an ogre who lives under a bridge that one must walk across, only they mistakenly perceive it as 'their' bridge and you will go by 'their rules' or listen to 'their invective' without regard for any sentiments of your own. They as a rule don't accept correction, or even engage in a dialogue, you are held captive by them until they are finished and crawl back in their hole(or wherever they came from).
Another image of a "troll" is one who goes from place to place "unloading" their particular spiel, seeing who will 'take the bait' and run at their idea. This image is conjured from fishing, where one 'trolls' with bait until a fish 'jumps on' and the fight ensues. It may be a particular doctrine, or insight but the one who 'takes the bait' is now obliged to battle the "troll", usually until some external entity tells them to "Break it off!"
A "Rhetorical Fallacy" could be caused by many things, and is not the exclusive domain of trolls: one could have incorrectly interpreted, miscommunicated, relied on tainted data, or innocently confused a source or interpretation. What makes them different from a "troll" is they respond to correction and indicate a willingness to learn; a "troll" merely reinforces their own skewed references and 'lashes back' at those who are patiently trying to inform them. "You Listen to ME" is the signature statement of a "troll", they have no inclination other than to unload whatever their invective is. They hold their audience "hostage", proving "they are right, and everyone else is wrong." They are generally "injured" or done injustice to, and misrepresented; and they are quick to inflict their exaggerated sense of grievence upon you.
It's not always apparent when you have a "troll"; there may be a legitmate difference of opinion, or one who is misinformed, but desirously seeking the truth.
"A soft answer turneth away wrath: but grievous words stir up anger."
If you "open your door for business", be prepared to meet all types of customers-in whatever frame of mind they happen to be in. A few of them are violent, obscene, or confrontational-these are why the "Flag" button exists. A Moderator has the tools to revoke their privileges and ban them from the site.
However, most merely have an "agenda"; a "troll" is usually identified when after a correction is suggested, they continue on unmindful or unwilling to any sort of reconsideration of their viewpoint. "DV to extinction" is the weapon of choice. You are basically saying, "Since you won't accept any adjustment, and are continuing on in your convoluted rationale, a consensus of opinion will make your answer disappear." If it is a question, a "VtC" may be in order.
Trolls usually are "Lone Wolves" and don't travel in packs. However, frequently they may represent a mainline doctrine, creed or practice and as such, a legitimate difference of opinion may exist. You may identify a particular individual as a "Troll", only to find that a considerable subsection of the viewing public agrees with them. If we are a "Learning Community", we can learn from one another and support the rightful conclusions, regardless of who makes them. We can also "respectfully disagree" and maintain a courteous dialog, not allowing our differences to define our relationship. Accepting a difference of opinion, but agreeing to continue to communicate, is a sign of maturity; if it doesn't involve a moral compromise, then it is part of the interaction this site encourages.
Trolls and trollism exists in the hearts of those individuals who demand an audience for their particular spiel. Since we are an "open" website, we are obliged and will frequently give an airing to those who's sole purpose is to vent their issue. However, after listening and objectively critiquing their responses, if they take no course of correction, and continue in their rants, then we do the community and the broader public a disservice by not DVing them. One must be mindful of the admonition of Gal. 6:1, and not fall in the trap of being harsh or critical-thus imitating the behavior of the one we're correcting. And let us all understand that amonst our participants a legitimate difference of opinions exist, in which we strongly believe, yet does not become the basis of our interaction. That distinquishes us from those who "Troll".