An innovation of
The first implementation was well documented by BikePortland.
The Federal Highway Administration and the Bicycle Technical Committee of the Manual of Uniform Traffic Control Devices (MUTCD) warned that "Insufficient information has been provided for the control intersection locations to determine if these locations are effectively comparable to the experimental locations. Control locations must have very similar or identical traffic & bicycle volumes, lane configurations, and traffic control (including comparable turning movement restrictions). The City needs to provide this information to FHWA for review & approval"
So the Initiative for Bicycle and Pedestrian Innovation is studying the uncolored boxes that have been installed. The good that came out of the FHWA involvement was that additional bike boxes without color were installed. Here's to hoping that the study shows good things for bicyclists.