I'm pretty sure most regular posters on this board realize they are to some degree accountable for their words. As an observer I frequent several professional boards where all users must use their real names. Even with their real names it's amazing how nasty things get with the absence of facial gestures and other non-verbal means of communication. With those gestures someone could quickly realize that someone was seriously hurt or worried and stop what the other was joking about, for example. As such I'm not sure "real names" add anything.
I'm also sure most posters don't want their posts to be google searchable. Google is evil