Just about every cyclist in the NYC footage wants to go faster than traffic, not slower. They are all passing motor vehicles. The vast majority of the perceived and real hazards would go away if the cyclists rode with the flow of the traffic. But no NYC cylist wants to do that, so why would they want separated paths and cumbersome intersections that also slow them down as suggested they might - they'd still try and 'beat' the flow thru hazardous passing and turning, made even more so by separated paths.

Al