B. Carfree

I think you are misunderstanding the objections. While these side paths do provide some protection from being hit by an overtaking motor vehicle, a risk that is overplayed imo (yes, I'm aware of the data and it appears to be mostly crap in an urban/suburban environment). At driveways, anyone proceeding on this path on a bike will find themselves out of sight, out of mind of most motorists who want to pull in or out of those businesses. Things can go south at those intersections in a hurry, partly because motorists mis-estimate cyclists speed by a large margin and partly because many of them don't really care.

Then there's the actual intersection issue. Cars making right turns are almost certainly not going to be looking for bikes coming along and cars making left turns are scanning the travel lanes, not several degrees further out, and also will often not notice the presence of bikes proceeding straight. The most dangerous place, intersections, just got more dangerous. These side paths effectively double the number of roads interacting at an intersection.

Lastly, there's the trip time thing. If one has to ride like a six-year-old in order to not be taken out at every driveway and must wait two minutes at each intersection, it's going to take a looooong time to get across town. Might as well drive if you have to go slower than a jogger.