I just came across this answer (10k only) on Ask Ubuntu. (Image Linkimage link). A new, one-rep user just posted thirteen "abusive" answers over fifteen minutes.
Another case: a user managed to post a dozen answers suggesting to install malware and by the looks of the comments from question authors, they were successful.
Is there ever a legitimate reason for a user, especially a new one, to post so many answers like that, especially on one question? Shouldn't they be on a more restrictive rate-limit?