In an action that went largely unnoticed last month, the CHSRA has changed the specifications for platform lengths. Whereas they were originally to be 430 meters (long enough for double trainset), they will now be just 800 feet (243 meters). This will effectively cut the capacity of the system in half.
The memo does allow for longer platforms at shared stations — if other operators are running longer trains. Its effect on the cramped Transbay Terminal is unclear, as Caltrain is only planning for 8-car EMUs.
The decision also affects placement of turnouts and crossovers. So once the track and platforms are locked in concrete, it would be extremely difficult and costly to change later on. Reducing costs of the project is one thing — but this is an example of being penny-wise and pound-foolish.