Today Nissan unveiled a pair of concept cars with radically different characteristics, created by a new approach to product development, that together offer a new take on authenticity. The IDx concepts on the Nissan stand at the 2013 Tokyo Motor Show are case studies. The first is a casual/lifestyle-focused vision, the IDx Freeflow. The second is IDx NISMO, an ultra-sporty model of the future that looks as if it came directly from a driving simulator. IDx...