DOT,  HART, and 30 years of consultants and studies are consistent in showing that without the rail an increase in the urban core to all residential development would lead to increases in highway traffic many times what it is today. So a prediction of LESS traffic than that is sobering. IOW rail will mitigate the traffic congestion to what is similar or slightly worse than today's congestion.

It's based on rail ridership surveys at the time of the study. So its not surprising that the design of the rail system will reduce traffic congestion to a point that today is intolerable. My personal opinion is that, if we can be realistic, is that if the rail design is good enough, that the survey ridership will be exceeded. People really do want to travel in comfort - swiftly and cheaply.