I haven't seen CAHSR talk about "Palmdale Base Tunnels" - whatever they are. They've talked about going through the Tehachapis with several tunnels, but no single large one. Even through Tejon Pass - they were going to tunnel to the top, cross the fault at grade, then tunnel back down to Santa Clarita. Tejon Ranch should want that, so they can have a top-of-the-pass station to serve their New Cities. "Base Tunnels" usually imply starting and ending at a similar elevation; the San Fernando Valley and Palmdale are a couple thousand feet apart in elevation, as are Palmdale and Bakersfield (Palmdale=HIGH Desert), so even if Bob2's Big Tunnel through the San Gabriels were built it would not be a "Base Tunnel" as commonly understood (it would be on a grade though not a ridiculous one). CAHSR's scheme from Palmdale is basically to parallel Metrolink with enough tunnels to straighten out Soledad Canyon - again, not a "Base Tunnel."

IOW, as we all know, Mouse is on a different planet.