Surely I can't be the first person to have thought of it, but Uncle Google suggests this hasn't been discussed before. Would it be difficult to make a preview button available when posting comments? Was it lacking from the software being used or is it just disabled? This blog uses different ways of text formatting than I think a lot of us are used to from other discussion forums, so if it happens to be easy to do, it'd be good to be able to experiment and see the results before making one's comment available.
I just tried that sandbox linked to from the wiki and it doesn't seem trustworthy, what should come out as italics comes out as some sort of a highlight...
Funny, I felt that bystander reluctance thing while posting this. "Why hasn't anyone posted this before? Is it because nobody wants to be the one asking for something? Or is it a silly request in some way I don't see now?"
EDIT:
I see Uncle Google failed me. Or is it that I failed Uncle Google? ;)
Thanks for the reponses, all.
It's a popular request. Search this thread for "preview" (it was requested multiple times). TrikeApps has declined to develop it so far for more or less the reasons Emile suggested, but the code that runs this site is open source, and contributions are welcome.