Hi Timo888,
Actually, the "history shows us" comment is incorrect. I don't claim to be an expert on this subject, but my partner certainly is. She is a graduate of MIT's urban studies program. There is an extensive research literature showing that increased congestion dramatically reduces automobile usage.
Through the 1970s, the idea behind urban planning was to keep making room for cars. We subsidize their use, build expensive roads and bridges, and spend a lot of money maintaing them. But the more rapidly we build, and the more we subsidize, the more rapid the uptake of private versus public transit.
Increases in congestion are inevitable in NYC as PlanNYC removes parking spots to make way for bike lanes. The same is true in San Francisco. But this very rapidly gives way to fewer cars and cleaner air.