Interesting points for sure. At some point I just say that sweating after a commute is something we have to deal with (same as getting fat by driving a car :-)). I'd rather bike and be sweaty than fat and driving a car (yes, I know not all car commuters are fat, but in generalities...).

The separated thing is super interesting to me. Obviously we couldn't do it on all streets, like the very skinny SF ones you talk about (I live near many of them in the Lower Haight). On those, which are not major thoroughfares, mixing bikes and cars is fine. But when it comes to a 4-6 lane street like Market St (or some in Chicago), separated makes sense. The traffic will go around if the street is less amenable to them. It's the same argument as taking down a freeway through a city. SF did it both at the Embarcardero (well, that one was by natural causes aka an earthquake), but then also at Octavia. Traffic slowed, neighborhoods revitalized. Studies have been done showing that taking these down doesn't greatly increase driving times, and often the traffic driving them doesn't actually stop in the city that they pass through. Instead they pollute the air and leave. Strong argument for taking them down, IMO.

But I've digressed. I agree there are challenges and never a one-size-fits-all solution. But there are solutions that are not currently being put into place that benefit the vast majority.

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