Is there more to Court Street’s success over the years than ‘flexible design’?

"Flexible design enabled Court Street to adapt to changes that could never have been anticipated by its nineteenth-century builders." (29) Brainard seems to be convinced that flexible design is the main, if not the only, reason Court Street was able to survive over the years. What about other physical aspects such as aesthetics? the stoops? the spatial enclosure of the street? Its human scale? He mentions some of these but doesn't seem to give them too much credit...