[xtian]

But "retarded" is in fact a different word than the alternatives you posted. Different words have different implicit and explicit connotations. So word choice and style of communication are entirely valid factors when evaluating whether an opinion is worth one's time given that we now live in a vast sea of opinions.

I suspect that people who think that how they communicate is distinct from what they communicate have not thought very carefully about the problem of communication.

What the word "retarded" communicates about the person who uses it is something I think you can work out on your own. It's one of many similar words that I often use accidentally when I mean something more precise.