Beyond the Walled Garden - the User Interface

Ryan Singer of 37 Signals (Basecamp, etc.) gives a presentation on effective User Interfaces:

http://www.slideshare.net/carsonified/ryan-singer

Which leads me to consider how you could even hope to show a user the level of information/control being managed beyond the 'walled garden'. Assuming you could somehow measure this level, the UI would have to be both complex (potentially showing numerous content areas/places) and simplistic enough to be utterly usable.

The worry is that people don't consider measuring the impact or regard it as too difficult.