whichever vague or codified 'rules of the road' are commonly held and followed by enough motorists to get the roads to function transportationally for them,

the vague but commonly held 'rules of the road' for bicyclists encompass a different set of 'rules' regarding collision avoidance, lane sharing and others that maximize the functionality of bikes in traffic.

Robert Hurst addresses this in his book.


The traffic dynamics affecting bicycling differ among cities (even within cities) in the USA to a greater degree than differences for motorists. if a mayberry driver gets plopped down in manhattan, maybe they will cope, but bicycling conditions are much different between mayberry and manhattan island.

Even within 21st century Mayberry USA, a motorist can move between a 25mph neighborhood road and a 55mph freeflowing merge/diverge arterial easily and with less change in operational rules, but a bicyclist will be presented with differences in functional 'rules of the road'- heck, even john forester endorses the distinctly unvehicular position of riding between faster lanes of traffic at certain times ....talk about different 'rules of the road'...

forestor is more mayberry and idylls of post-war Britain, Robert Hurst is much more 21st century and Manhattan.