This layout example allows developers to have multiple independent controller display panels in addition to the current state that the app is displaying. A user can move between states and preserve panel content without creating messy and slow nested states. Panels have independent scopes. To share the scopes remove the "scope: true" parameter in the directives.
The Problem with Angular UI Router is that you can only display one state on a page at a time. AngularJS Multi Panel Routing attempts to fix that.