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After all the discussion on SOPA/PIPA/ACTA here comes a guy and tells us that we should all "select comments" or use "pre-moderation" because it is good for the quality of the discussion. Am I still reading the same site?
With such a broad definition as you propose, any opinion the site's owner doesn't agree with can be classified as "trolling". Sure, with appropriate measures the "discussion" can look nice and tidy, as if everybody has agreed with everybody else. But, what's the point of discussing a topic if you are never confronted with different point of views and opinions?
This is the reason why trolling, as it was originally defined, takes intent into account. Essentially anything except for vandalism and spam is exempt from it because no one can ever decide what is trolling and what is just an adversary opinion.
Point systems help (ideally users should +/-1 comments they read but it should be the authors karma that should be displayed next to it) but they aren't perfect. Especially in niche communities which are biased because of their interests.
Anyway, my point is, let others express their opinions and accept some level of trolling as a fact of life. Sure, do eliminate vandalism and spam but other than that just focus on building the community, not on limiting it.