Many traffic jams are caused by a phenomenon called a traffic wave. One way to mitigate this problem is to have drivers pace themselves better.

There are documented cases of good samaritans playing this role and helping everyone to get where they are going on time. This too sporadic to make a long term difference.

City sponsored cars would be a more consistent alternative. The cost of this program would be offset by the savings required to upgrade highways. Instead of hiring new city employees and new vehicles, the city could crowd source this job and monitor performance with GPS.
-- ixnaum, Oct 08 2017

Traffic waves website http://trafficwaves.org/
by [wbeaty] [notexactly, Feb 16 2018]

random, halfbakery