Tom,
I seem to recall that you did some heavy editing in a post last month:
http://www.coffeecup.com/forums/users/3 … #post99738
When first posted, it was something completely different, in fact with an almost opposite sense. As result, I posted a rather meaningless, cryptic response with allusion to contradiction and editing...
(There again, maybe I was dreaming the whole thing, so please correct me if my mind was playing tricks on me and I got it all wrong...!

)
Anyway, I don't see why any editing needs to be possible at all. Once posted, it should stay. If changes are needed, just post again. The preview is quite enough to allow proofing.