Explain to me how you are doing me a favour by riding in the middle of the road at 20km/h effectively cutting off an entire lane to the rest of use who have paid to use it?
You have just described Melbourne tram. Relatively speaking trams cause far more congestion on Melbourne roads (think Burke Road, Toorak Road, Glenhuntly Road, Hawthorn Road, Chapel street etc) than the odd cyclists. In Europe they have electric trolley-busses that pull over like a bus - a much better idea on shared roads. Add tram lines impact on road safety (motor cycles and cars are also affected). Add tram line maintenance costs and specialist personnel required to maintain trams and drive them.
And the only reason a cyclist might block a moving car is because the left most lane is already blocked by a parked car. I can use an argument that roads are built for going, not for parking. Clear the roads from stationary objects and you have a much smoother, fairer traffic system for all. When I lived in USA on East coast I noticed that most roads with one or two lanes there do not allow kerb side parking, period. Fix the road parking problem and we all can share the roads better.
And the only reason a cyclist might block a moving car is because the left most lane is already blocked by a parked car. I can use an argument that roads are built for going, not for parking. Clear the roads from stationary objects and you have a much smoother, fairer traffic system for all.
Not where I live. We have clearways the whole way to the city during rushour. But one solitary cyclist can effectively cuts three lanes down to two because no-one can get around them.