> Personally, as an SF resident I would much prefer all the cars to be tunneled or elevated instead of idling in front of my house or blowing loudly through my

> Personally, as an SF resident I would much prefer all the cars to be tunneled or elevated instead of idling in front of my house or blowing loudly through my block. It's a safety issue. This is a false choice though. It would be better to design the city in such a way that we don't need personal automobiles for most trips. Building high-speed roads (elevated or not) through a city tends to have the opposite effect. If you live in SF, just think of the parts of the city that do have high speed roads. Is it pleasant to walk along division street? People choose their mode of transit based on what feels safe and convenient to them. In the space and money taken up by an elevated highway, we could have low-speed mixed-use streets and an entire separate highway for bikes, and it would be safer and quieter.