Chicago-Detroit will also be by train. In theory we could tack on coach seats on Amtrak's Wolverine for no additional cost, as Detroit straddles a zone boundary and for point-redemption purposes is the same place as Chicago. However, it would mean trusting the four-hour connection at Chicago and arriving in Detroit at 12:18 AM, and also require that we be on the train at Detroit at 6:28 AM in order to meet our connection at Chicago. Now train stations don't require airport-style, arrive-two-hours-in-advance security, but I still don't like being up that early the day after a convention if I can avoid it, so we'll go ahead and spend the extra money (only $123) to purchase the other tickets and for the extra hotel nights at Chicago coming and going.
We could of course catch the train at Reno if we wanted to spend $200 on taxi fares to and from Reno from Fernley, but we'd miss one of the major scenic highlights of the trip. We can park long-term at Fremont and catch the Zephyr out of Emeryville as we have done previously. Also, I have commitments in the Bay Area on the days at the end of the trip, so it's just as well to end the trip there instead of Reno and Fernley.
A reassuring element of train travel over air is that these tickets are fully refundable until the departure of the booked trains; that is, if we change our minds, we get the points back. It's not like air travel where if you make one mistake, your money evaporates and you're stuck.
I'm looking forward to this trip. It will be our third (and fourth) times on the Zephyr. It's the first time we've gone east and west on the same route, but we couldn't work out a routing that would take us over one of the other routes (the only big east-west route we haven't done is the Empire Builder) and still fit the needs of the rest of our schedule.