I was a moderator on a highly used board that used vBulletin and we dropped the members having the ability to delete posts for 2 reasons. 1, when deleted no one can see that it is gone, so people would post something bad, let a few people get mad then delete it acing like they never posted. The other was that people were deleting posts all the time for whatever reason then the staff was bombarded with requests to delete any reply that had the deleted post quoted in it or delete the quote. Allowing people to delete their posts led to more trouble and work then the problems it solved or work it saved. At least now if someone edits their post and just puts "Deleted", people know it was their and the author edited it. Again that was from my experience and it may or may not be the same problems here.