A claim made in a Facebook comment stream (a discussion of a complaint about the indicative being used where the mandative subjunctive is supposed to be the only correct choice, if you must know):

The number of people, who are doing something incorrectly, is not a determinant of the correctness of the act.

My response: in math, yes. In language, no.

(Is it rude to point out that the above claim contains commas that would best be omitted? Yes, it probably is ...)