That sounds good to me, thanks Sam for looking into this.
I was wondering about the web crawlers, will they see a hidden post with just a “hidden” message the way a human would with a normal browser, or would they also see and index the potentially inappropriate content that is hidden with CSS?
Another related issue is the post revision history, I know it could be disabled for normal users, but some users do like and use the feature for normal edits of inoffensive posts. A user actually suggested that it would be good to hide the revision history button on posts that have a flag hit on them. Otherwise users can (and will) go back and see the original offensive post.