I welcome comments here, especially from people who disagree with me. There is one rule that I ask commenters to follow -- please do not make personal attacks on other commenters. Such comments tend to cause discussion to degenerate into a slanging match so I will usually delete or disemvowel them. If you think some other commenter is dishonest or stupid, you should show us, by presenting evidence and letting the rest of us make up our own minds rather than telling us.
Trolls are posters who try to disrupt the discussion by posting specious arguments, inflammatory comments or off-topic material. The best way to deal with trolls is to ignore them. Trolls will usually get bored and go away if no-one responds to their provocations. If you respond to a troll, I will probably delete your response and the troll's original comment.
It is perfectly fine to use a pseudonym when you comment. What is not acceptable is the same person using multiple pseudonyms, or sock puppets. Such behaviour is likely to result in your real name being posted along with the names of all your socks.
If your comment does not appear right away, it probably got caught in the spam filter. Be patient, that just means that I have to approve it. Whatever you do, don't submit it again because that will really convince the filter that you are spamming. If you register and login your comment will bypass the spam filter.
You can format your comments using Markdown or HTML, but I recommend Markdown. Here is all you need to know to use it for commenting: separate paragraphs by a blank line and this example
> Quote some text with a [link](http://example.com).
*Emphasis.* **Strong emphasis.**
results in
Quote some text with a link.
Emphasis. Strong emphasis.
This page lets you play with Markdown, and see how your text appears.