Since the spam is all in one place, eliminating the need to go into individual threads to delete replies, it cuts down on the workload for the mods quite a bit.
The annoyance of visible spam before the rounds are made should be pretty much eliminated, and no one has to be up at odd hours of the night to delete posts. I've manually tested the filter in every board and sub-board, for creating threads and replying. It is a little bit annoying for new users with no posts yet to have to wait a day or so for approval, but once they have one approved post it won't affect them anymore, so I think it's a worthwhile tradeoff considering it has already begun preventing spam.
By the way, CAPTCHA is enabled for new threads, but it's ineffective at eliminating spam because many spammers are actual humans.
