If someone’s writing 627 comments in a single day — their first day! — that’s probably a spammer. It’s not 627 comments on SEL and ML, but across this person’s Disqus account.
This has been a problem for some time now with Disqus. Some idiots think they can just bludgeon blogs left and right with tons of comments … and they can.
I wrote a similar post here a little more than a year and suggested that Disqus simply put a limit on how many comments new users can post.
Disqus staff read the post and joined the conversation in the comments, but that suggestion seems to have fallen on deaf ears.