Hi the basically problem is the tube under San Francisco Bay and CBTC will definitely get them some breathing room but as most cities in the world the population is growing and eventually CBTC will not helped much and all, the answer is a new tunnel under San Francisco Bay?. It's gonna be expensive but I don't think you've got any alternative. The Bart people must regretting not having 4 tunnels instead of two because that would help a lot.
