If you reserve separately, you can print separately as needed. If you use the multi-city option, the tickets would all be printed together, but still refundable separately (as per the above restrictions).
Normally, I'd do that, but in this case, they're all being mailed to me as none of the locations are staffed. It wouldn't make a difference, so I was going to save some hassle and just do it all in one transaction. (The only other time I'd book everything under one itinerary is if the initial station is staffed but the return station(s) aren't, in which case the separate bookings from the return station(s) would be mailed to me, negating the savings of printing them separately. This was the case with my LAX-PRB booking for last week.)
However, it just occurred to me that Amtrak now lets you mark tickets as being for pick-up from a Metrolink ticket machine. I haven't checked to see if this is allowed for SIM, but if so, I think I will book that last segment separately so that I can avoid having it mailed, and thus printed, and can therefore get a full refund if she doesn't need to use it.
I'll probably still book the LVS-PRB and PRB-SIM runs as one itinerary so that we only have to track and find one Amtrak envelope being mailed.
(BTW, thanks for all the replies about 100% exchange vs. 90% refund. However, I am familiar with Amtrak's refund/exchange policies on printed tickets--I was specifically asking if you could refund an unused
part of a
single booking after travel has begun. I suppose I should have known the answer already (and I suspected it as such), as each ticket has that specific segment's value printed on it (unlike an airline ticket, where routing plays virtually no part in actual fare), and that would be the amount you would receive in the form of an exchange voucher, which I'd likely take over the 90% refund...it'd force me to fly back down sometime in the next year and take Amtrak to use it!)
What would interest me would be a comparison of the price, separate legs versus multi-city. On some routes there is a substantial savings with through routing, but not always.
What I've found is that multi-city itineraries breaking up a trip that would otherwise be a through train makes the costs go up, but if you make the connection points at places where the system would naturally make you connect to another train, there's no price difference.
In other words, if I booked SAN-CHI using just the one-way function versus SAN-LAX-CHI using the multi-city option (to include a two-day layover in L.A.), the price would be the same, as either way, I would be detraining in LAX and then connecting to another train there.
However, if I booked SAN-LAX-FLG-ABQ-KCS-CHI (either with no layover at each place or with a week between trips, assuming all of the fare buckets are the same), I would end up with a very expensive ticket.
However, something just occurred to me. I think that ARROW looks at available
through inventory when calculating the applicable fare bucket. This means that if, let's say, 299 seats out of 300 are booked on the very short segment LAX-SBD on the SWC, and SBD-CHI is completely empty, if someone goes to book LAX-CHI, they'll be quoted the highest bucket price for that route.
If it were possible to identify which segments have more bookings (in our hypothetical, the LAX-SBD segment), you could use the multi-city function to ticket them separately--in other words, LAX-SBD (on which you'd pay the highest bucket) and SBD-CHI (on which you'd pay the lowest bucket). The sum of these two separately-ticketed segments should be less than the single high-bucket LAX-CHI price.
Of course, loads are probably rarely bottlenecked on such a narrow section of the route, and if one section is nearly sold out, there will most likely be others that are up at high bucket too. Plus, trying to figure out which section is making the bookings jump up is probably more hassle than it's worth, as it would involve a LOT of fake test bookings (unless you know someone in Amtrak's revenue management department that could drop you a clue).
Anyone had any experience making this work to his or her advantage?