Suggestions that the San Joaquin trains be extended through the Tehachapi, are little more than a Railfan's wet dream and ignore the reality of the situation. Los Angeles to Bakersfield, via Interstate 5 and Tejon Pass, is 2 1/2 hours most days. The all-rail route via Tehachapi & Mojave is 4 hours. Also to be considered is the extra rail equipment needed for the extended operations. Simply put, the bus is used where it does the most good, in a straight shot over the mountains. This idea was first practiced by the "pro - passenger train" Santa Fe way back in the 1930's and the days of gas-powered buses traveling a 3-lane U.S. 99 over the Grapevine.
The San Joaquins are a rare example of a state agency ( Caltrans rail ), and a Federal "Thingie"( Amtrak ), doing something that actually benefits the tax-paying public. Let's leave it alone.