Remember, the
Acela trainsets have been in service since 2000. The
Brightline trainsets entered service in 2018. That's nearly a 20-year difference. Granted, I'm far from an expert on semi-permanently coupled trainsets and what exactly was doable in those days, but I doubt that Amtrak would take an entire
Acela trainset OOS for one car unless they had no other option. They may not always be the most efficient, but I find it difficult to believe that the transportation and mechanical departments would be that idiotic.
As for the idea of fixed trainsets in general, I certainly see the appeal. There's always a risk when going over the couplers, especially with the moving footplates and various hard edges to fall on. At the same time, it can potentially be a nightmare if a trainset or even a pair of cars (like what Illinois is doing) have to be taken out of service because of an issue on just one car. Granted, Illinois ordered some individual coaches in an apparent attempt to help mitigate the issue, but the cafe and business class cars are still in pairs with coaches. If you lose that pair, you better hope you have another handy.
Below is the planned setup for the Siemens cars operating out of Chicago. Please note that the " - " indicates a Type H coupler while a " / " indicates a semi-permanently coupled married pair:
Locomotive - Individual Coach - Individual Coach - Coach/Cafe - Coach/BusEcon - Locomotive
This is the CalTrans setup:
Locomotive - Coach/Coach/Coach/Cafe/Coach/Coach/Cab Car
Here's a breakdown of who ordered what:
Customer
Car Type
Quantity
Description
# Doors
Coupler
Configuration
Caltrans
CT-1A
21
Mid coach car
2
S-S
Caltrans
CT-1B
7
End coach car coupled to locomotive
4
H-S
Caltrans
CT-1C
7
Mid coach car with wheelchair lifts
4
S-S
Caltrans
CT-4A
7
Cab Car
2
S-H
Caltrans
CT-5A
7
Café Car
4
S-S
IDOT
ID-1A
20
Individual coach car
2
H-H
IDOT
ID-1B
34
Coach car for business or café married pair
2
S-H
IDOT
ID-3A
17
Business/ economy car
4
S-H
IDOT
ID-5A
17
Café Car
4
S-H
As you can see above, only IDOT has taken steps to have spare equipment available to mitigate any sort of impact from a bad ordered car. All of CalTrans' cars will be semi-permanently coupled. Now, I don't have any sort of data that would indicate the primary causes of bad-ordering, but I figure that if CalTrans didn't feel the need to have individual replacements on hand, a large part of the concern could be weather-related, as we tend to have worse weather (the current snowstorm, for example) than California does.