One day when I was a junior medical student, a very important Boston surgeon visited the school and delivered a great treatise on a large number of patients who had undergone successful operations for vascular reconstruction. At the end of the lecture, a young student at the back of the room timidly asked, "Do you have any controls?" Well the great surgeon drew himself up to his full height, hit the desk, and said, "Do you mean did I not operate on half of the patients?" The hall grew very quiet then. The voice at the back of the room hesitantly replied, "Yes, that's what I had in mind." Then the visitor's fist really came down as he thundered, "Of course not. That would have doomed half of them to their death!" God, it was quiet then, and one could scarcely hear the small voice ask, "Which half?"
Districts have to help bring the resources of a city down to where they are needed by street neighborhoods, and they have to help translate the experiences of real life, in street neighborhoods, into policies and purposes of their city as a whole. And they have to help maintain an area that is usable, in a civilized way, not only for its own residents but for other users—workers, customers, visitors—from the city as a whole.
To accomplish these functions, an effective district has to be large enough to count as a force in the life of the city as a whole. The “ideal” neighborhood of planning theory is useless for such a role. A district has to be big and powerful enough to fight city hall. Nothing less is to any purpose.