@trevor got to agree with you on that. You always have to think of your end users here or at least give the option to dumb down the composer view. 98% of users in my forums are middle aged non-tech guys. They like boring kitchen sinks, big buttons to insert links and so forth. They also like one place to type. It's really not supposed to be a tech demo.
Double panes is a cool option that may be applicable to a certain demographic but it will be a small one.