I love to see polite responses like this on help groups. So often I see complaints about people being incompetent or not reading manuals or whatnot. Being polite is wonderful and what's needed if you care about having a good relationship with folks out there. People aren't morons just because they make mistakes. Everyone makes mistakes.
Maybe rude responses are more likely for projects that feel they already have all the attention they want and just can't keep up?
Sorry for not spending the time to look up a counter-example on rudeness, but the polite example is nicer to read anyway. And I guess finger pointing isn't nice either, so maybe it's just as well I haven't looked one up. I guess I could anonymously quote or something.