The Guardian has just done an analysis on comments and they get approx 2% that are blocked or deleted. So it doesn't look like they're fighting back the hordes

The Guardian has just done an analysis on comments and they get approx 2% that are blocked or deleted. So it doesn't look like they're fighting back the hordes and you just can't see it. And in the article, the chap says that removing the spammers and swivel-eyes is easy. What's hard is curating the discussion. If you read the comments on this article and on similar articles recently, this is the area that attracts the main criticism of the Guardian moderation. My guess wrt Reddit is that it's a much more difficult job to remove the spammers and front-page optimisers. The curation of a sub-reddit, if it happens at all, is probably easier as there'll likely be little or no real need to be subtle about it.