That will definitely run into trouble any time we get a somewhat intelligent, but destructive person. They can and will take advantage of that, as their intelligence allows them to predict what other people will be watching out for. It's no different from a bully making sure their bullying never crosses a line that the teachers will notice, but still successfully spreading the suffering. You've become that teacher that only stops the big fights but allows the rest. It's just not easy stuff, that's all, for that teacher or for mods.

My first trolling was when I was a kid, I played Starcraft on battle.net. This was before even Brood Wars. I was a very angry teen, a little bit sadistic, and I liked making people suffer as much as I felt I suffered in my daily life. So I would go into 5v3 cpu matches, that's 5 humans vs 3 AIs. These were very laid back matches, people just relaxing and shooting the shit, super easy. I would backstab them, always making sure my team lost. I enjoyed it, it was fun. For me, not them. I was a bully, and it was all about that feeling of power that I completely lacked in real life.

I did a lot more as I got older, I graduated to more harmful things than pissing off Starcraft players. I eventually grew out of it, of course, I'm no longer a little shit. But it was fun to ruin the fun of other people. Hurting people is fun. It feels good to hurt people. That's the problem.

I understand wanting to give people the benefit of the doubt though, especially while we remain a fairly small community. I really would consider using logical fallacies as a litmus test. That will catch all but the best of them. It's very hard for me to intentionally piss you off solely with rhetoric if I can't pretend you're something you're not, and can't put words in your mouth.

And besides, a little more public education on logical fallacies wouldn't hurt. A short temp ban for strawman probably wouldn't really piss off someone if they did it by accident. It'd be kinda meh, whatever. If they kept doing it, that's a troll with very high certainty. Otherwise they'd learn, it's not a complicated concept to grasp.

Now that UM is gone, he's a fantastic example to look back at, incidentally. We have strong evidence of him being a conservative: He made around a half dozen posts to the local Conservatives community maybe a month ago. Was affiliated with BYU, which is a Mormon university that mandates religious education, you cannot be admitted to that college without a ranking religious figure writing you a letter of recommendation, it's part of their admissions process. He would post Fox News links.

Yet despite that all, he consistently claimed positions that, if true, would have made such environments deeply unpleasant. That's all circumstantial, though. It's not proof. But if you go through his comment history, you will find TONS of strawman arguments. He loved telling other people what they were, what they were doing, what they were saying. He would not listen to a person saying what they were, what they were doing, what they were saying. He would tell them, as if he understood them better than their own words. Strawman, all over the place.

edit: Just thought I'd add, it looks like UM tried to get around his recent ban with a new alt. This time he started up a community called "Conservative Voices".