I don't know all potential routes in a 20 mile radius of my home, no. In a large metropolitan area, there are literally many hundreds, if not thousands of miles

I don't know all potential routes in a 20 mile radius of my home, no. In a large metropolitan area, there are literally many hundreds, if not thousands of miles of roads within such a circle. And something changes every year. Sure, someone who does nothing but ride, day in, day out, like a bike equivalent of an old school taxi driver, would learn them all after some time. I don't have that amount of time to spend. I don't see traffic jams formed by bikes, no, but I regularly see construction crews regularly closing bike lanes and bike paths for work, for parking their construction equipment, or for setting up temporary signage.