I don't know if this has been mentioned previously but I know of some other forums where apart from the moderator who can delete any post or thread at any time, an individual member can delete or amend his or her own post but must do so within a certain time limit, say 2 hours. So that gives the poster time to reconsider his/her post and change or delete something that perhaps shouldn't have been said.

That system seems to work very well where I've seen it used.