The good news: Caltrain has initiated a small study effort to develop a level boarding roadmap, as part of its portfolio of capital projects.
The bad news: in the summary of this study, Caltrain shows no sign of grasping the purpose of level boarding. We might need to display it on a freeway billboard, like this:
Caltrain does a very nice job of explaining the benefits of electrification. Faster acceleration leads to shorter trip times, a strong message that they hammer often. On level boarding, however, the messaging is muddled. It's something-something about steps? Easier and more inclusive access?
It's about shorter trip times, just like electrification. While electrification saves time in motion, level boarding saves time at rest. The savings are big: cutting station dwell time from 45 seconds (typical for Caltrain today) to 30 seconds (typical for BART, which has level boarding) is worth almost as much "acceleration" as electrification. Electrifying without level boarding is half-baked, and Caltrain should be spending a lot more on level boarding than distractions like BEMUs. Please return to your core mission to quickly and efficiently get people where they are going.
About these numbers: the diesel trip time is for an all-stops local with 45 second station dwells and 15% padding. The EMU trip time has the same dwell and padding assumptions. The level boarding time assumes that station dwells drop to 30 seconds, and padding is cut down to 10%. The lower padding is appropriate because level boarding not only makes dwells shorter, but it makes dwells much more consistent and predictable, as discussed previously. If two wheelchair users need to board, it takes the same 30 seconds, not five minutes of staff assistance. Here are the detailed stop-by-stop stats and string diagrams if you want to tinker with assumptions.