You probably haven’t heard of the ACE Train. It hardly registers a blip on the California transportation radar, shuttling commuters between jobs in Silicon Valley and places to the east where they can afford to live, like Livermore, Tracy and Manteca. But the ACE Train is a rare example of successful transportation in California. The key to its success lies in its functionality; it gets people where they need to be. Zocalo Public Square columnist Joe Mathews says rail planners with major agencies like LA Metro, Caltrain and BART should be taking note.