Most commuting in the US is done on highways, no at-grade crossings, and most congestion is caused by the imperfection of humans driving (look up rubber banding

Most commuting in the US is done on highways, no at-grade crossings, and most congestion is caused by the imperfection of humans driving (look up rubber banding effect on traffic). Self driving cars can use the same 4/5/6 lane highway MUCH more efficiently than mere mortals can...