Comment by Reason077

What tends to happen in London is about 90% of cyclists use the bike lanes, while a few racing-bike hotshots will skip them (especially when congested) and use the car lanes. Usually those guys are easily fast enough to keep up with the cars on busy city streets anyway. There's certainly no rule, real or imaginary, that says if bike lanes exist then cyclists must use them. But having decent cycle lanes there absolutely does encourage more people to cycle!