You can solve traffic grid problems only for a short term. Is it worth it, yes. However its not a lasting solution. The problem is the roads and cars itself. Its should continue being our primary source of transport for our city and any city. We spend on average 50 billion a year to build new roads in the greater Nairobi area. Temporary relieve until people buy more cars and the vicious cycle repeats itself. In 20 years we will be doing 10 lanes overpasses etc to mitigate the same traffic jams. Time to shift to a dedicated street level commuter train service that carries X10 more people, has no traffic jams and has zero pollution due to use of electric power. Lakini wapi ministry of transport officials have bought second hand diesel locomotives for piecemeal route service.