Connection reliability really must be evaluated on a connection by connection basis (as Amtrak itself does) not by broad brush assumptions.
The guaranteed connection between the Coast Starlight and Sunset/Texas Eagle is surprisingly reliable, despite the short connection time, shorter than Amtrak's general 60 minute guideline for providing the guarantee.
Since 2/422 only runs three times a week, they really do not like to pay for a couple nights hotel for misconnecting passengers, since there is not a train the following day.
The connection is protected by the following practices:
1. There is almost an hour of schedule pad for the Starlight's arrival in LA.
2. If enough delay is incurred south of the Bay Area to endanger the connection, Amtrak will "bustitute" connecting passengers to cut the corner. Usually they'll take connecting passengers off in Oxnard and bus them to Ontario to catch the Sunset/Eagle.
3. If the Starlight incurs significant delays north of the Bay Area, Amtrak will reroute and reticket Starlight passengers connecting to the Sunset/Eagle onto the San Joaquin train/Thruway bus route via Bakersfield. That is hours faster than the Starlight between Emeryville and LA.
Also, if the connection is made, but close, they will often spot the Starlight across the platform from the Sunset so all you have to do is walk across the platform.
Checked baggage is handled just like the airlines, Amtrak will handle the transfer.
Finally, note the connection guarantee only applies when both trains are on a single reservation number. If they are separately ticketed, you're on your own.
