In London, bicycles effectively use about 2MPG of diesel by slowing large numbers of buses and trucks to the position where they are unable to get out of low gear. They are one of the biggest causes of pollution from diesel.
If you got the damn bikes of the road, the diesel vehicles would pollute far less.
Yeah. Damn those bikes. We'll ignore the effect of the pedestrians, lights, junctions, general congestion and all the other factors that contribute to stop/start traffic.
And, as for public transport - sure, take your desktop computer, server or laser printer (or even your weekly supermarket shopping) under your arm on London transport in the rush hour. You can post the video on Youtube afterwards.
You know, the number of times I've taken my desktop computer to work, along with my weekly shopping, makes me glad my town barely has public transport. It would be a daily grind for me to lug all that around.
And I can testify that most of the single occupancy cars blocking the roads have a similarly burdensome commuter load.