NC just because I do all the time.
In the olden days of the internet (about 5 minutes ago, it feels like) "trolling" didn't mean "making things up for shits and giggles" or "harassing, threatening or abusing people" but to derail a conversation by posting obviously inflammatory or faux-naif basic questions/comments, or derailing by any means necessary. This wasted posters' time patiently responding to questions that had been answered a million times before or to exaggerated lines of argument. Didn't matter how sensible the responses were, the goal was to derail the conversation so literally any response was a win for the troll and a loss for the regular posters.
Hence the advice "don't feed the troll". Just ignore, ignore, ignore.
Grey rock.
Obviously no-one trolls on MN as they get instantly reported... 
But even as a casual visitor to these boards I do see the same arguments being started, the same time being wasted, the same things being repeated. It would be lovely and far more productive if threads could stay relatively on-topic, perhaps starting and linking to new threads if a new topic arises. Or old ones if the same old questions arise....
Anyone agree with me?