Another problem with this is, if a doctor or an airplane maker screws up, I can abandon them and go for a replacement immediately. With politicians I'm pretty much stuck until the ignorant masses change their minds.
That's why I'm a believer in highly federated, localized "competitive government".
I agree that democracy fails when it becomes too large and too centralized.
That's a cool idea. Competitive government can also be considered "scientific government" in a way, since different systems will be experimented with and the outcomes observed. I wish states would consider using something like charter cities (
http://en.wikipedia.org/wiki/Charter_city); cede some land to an organization and let them organize it on their own terms.