https://www.mercurynews.com/2020/02/19/carpool-lanes-not-planned-for-clogged-central-expressway-roadshow/

Q: I have never understood why there’s a push to build BART from the Diridon Caltrain Station to Santa Clara (duplicating Caltrain) when the dream of rapid rail around the entire bay could be completed at significant savings by ending BART at Diridon.

If there’s extra money, build a BART spur line to Norman Y. Mineta San Jose International Airport instead.