Airport trips on BART (either airport) have a supplemental charge that jacks up the price. The author is right in that our local transit agencies do not communicate, or at least their schedules to not coordinate. This is something the MTC has been looking into for the next generation of Clipper cards. They would like things to work like a German transit association of agencies, i.e. it will be transparent to the user and work as if it were one agency. That means one system of fares for the nine county region. The discussions should be interesting... Wear protective clothing.