I doubt if it's ever been illegal anywhere in the world. Au contraire, I think once upon a time, back when formal grammar was a compulsory part of the syllabus for all school kids, school teachers used grammar baiting as a normal part of testing and teaching grammar. Not such a bad method if the student knows how to look up the answers and work out the logic.
This post was edited by Benedict Arnold at December 24, 2017 9:58 PM MST
Grammar-baiting defined: purposefully posting a typographical error that the author knows, expects, or suspects will catch Randy D's attention, and in turn cause him to respond in kind. ~