On the other hand, if you can politely let the offender know that their spelling, grammar, punctuation, etc. makes it hard to read, and hard to read posts are often ignored... I see nothing wrong in letting the general members self police the board.
We had a big public discussion (275 posts) about this rule change, back in early 2006, IIRC.... Yup. here
Read at least the first post of that thread to get an idea of what the rule is about.