http://www.defenseone.com/technology/2014/04/why-there-will-be-robot-uprising/82783/?oref=d-dontmiss
Cars & trucks with on board A.I. could certainly improve efficiency, but it would mean giving up on human control. Even with standard or conventional vehicles operated by people, a supercomputer could dramatically assist & improve local & regional traffic flow.
http://en.wikipedia.org/wiki/List_of_motorways_in_the_United_Kingdom
http://www.ibtimes.co.uk/happy-birthday-m25-25-facts-infamous-motorway-239455
The M25 is the quintessential highway belt for Greater London
http://www.bbc.com/news/uk-25619343,
http://news.bbc.co.uk/2/hi/uk_news/england/west_midlands/8401336.stm,
http://www.bbc.com/news/uk-england-beds-bucks-herts-27019957,
http://www.dailymail.co.uk/news/article-1045177/Fathers-4-Justice-protester-arrested-M25-stunt-causes-15-mile-traffic-jam.html
http://jfdatalinks.blogspot.ca/2014/04/the-autobahn.html
http://jfdatalinks.blogspot.ca/2014/04/controlled-accesshighwaydefinition.html