Also, I'm not looking to eliminate the trolls in the world -- forced anonymity wouldn't CURE it, but would almost certainly lessen its presence considerably. However, having seen first hand how entirely unnecessarily negative attacks can destroy a community.
You bring up an interesting point though, in that speech can be 'moderated into existence' -- which in my opinion, is even more oppressive than public identifiability. You would institute censorship to restore anonymity? I consider that the worst of the two ideas.