There are a lot of terrific blogs out there on the world of writing, but Heart of the Matter isn't one of them. HOTM primarily covers politics, language as it influences politics, and politics as an exercise in branding and marketing, with the occasional post on some miscellaneous subject that catches my attention.
HOTM has a comments section. Sounds simple enough, but as even a cursory glance at the comments of most political blogs will show, many people would benefit from some guidelines. Here are a few I hope will help.
1. The most important guideline when it comes to argument is the golden rule. If someone were addressing your point, what tone, what overall approach would you find persuasive and want her to use? Whatever that is, do it yourself. If you find this simple guideline difficult, I'll explain it slightly differently in #2.
2. Argue for persuasion, not masturbation. If you follow the golden rule above, it's because you're trying to persuade someone. If you instead choose sarcasm and other insults, you can't be trying to persuade (have you ever seen someone's opinion changed by an insult?). If you're not trying to persuade, what you're doing instead is stroking yourself. Now, stroking yourself is fine in private, but I think we can all agree it's a pretty pathetic to do so in public. So unless you like to come across as pathetic, argue to persuade.
3. Compared to the two above, this is just commentary, but: no one cares about your opinion (or mine, for that matter). It would be awesome to be so impressive that we could sway people to our way of thinking just by declaiming our thoughts, but probably most of us lack such gravitas. Luckily, there's something even better: evidence, logic, and argument. Think about it: when was the last time someone persuaded you of the rightness of his opinion just by declaring what it was? Probably it was the same time someone changed your mind with an insult, right? And like insults, naked declarations of opinion, because they can't persuade, are fundamentally masturbatory. And masturbation, again, is not a very polite thing to do on a blog.
Argue with others the way you'd like them to argue with you. Argue with intent to persuade. Argue with evidence and logic. That shouldn't be so hard, should it? Let's give it a try.