Depends where you are but some cities easily have the density suggested there. > In reality, the effective space taken by cyclist on genera purpose road is big

Depends where you are but some cities easily have the density suggested there. > In reality, the effective space taken by cyclist on genera purpose road is bigger than a car — you need a huge safety margin to overtake a cyclis More than a car? I've certainly not been given more space when people overtake me. Remember a car is 6 feet wide, that's quite a bit of space already that's taken up by a car.