Xplo, this isn't meant as a personal attack, but you are terrible at giving advice. "The way to not do the thing you are doing is to stop the thing you are doing and not do it anymore". Usually, when people ask that kind of question, they are looking for insight and/or mental exercises to help them cease their behavior.
Well yeah, it sounds bad when you put it that way! Geez, way to trivialize my experience and stuff.
Look - let's just say Cetera's a self-righteous dick, for argument's sake. But he knows he's a self-righteous dick, right? So obviously he can tell when he's about to do self-righteous, dickish things - like that post he knew better than to make, but then he made it anyway because he wanted to be right on the internet.
So I guess what I'm saying is, next time he knows better than to post something, don't fucking post it, no matter how awesome it sounds. And there's no real secret to doing that except to practice self-awareness and self-control, like I said. There's nothing you can buy at the store that makes you less of a dick. There isn't any secret ninja zen that you can practice in your car on the way to work. I'm not holding out on him. "Just stop" is the only advice I have. That and to not get discouraged if it's hard.
I mean, I dunno, he could try some introspection, or see a counselor or something, and try to figure out what makes him want to be a self-righteous dick to people on the internet and how to deal with that, and maybe develop some better coping mechanisms or social skills or something. But I can't help him there; his issues are HIS issues.