Dunno... the three business cars mentioned all serve slightly different purposes.
"American View" is a track inspection car. It's the most likely to be used, probably by Engineering more than by an executive showing off Amtrak's facilities to VIP's. There will always be a use for this type of car.
"Beech Grove" is your traditional 1900's business car. A small galley & private dining compartment, two bedrooms, and a 6-8 seat parlor section. It's perfect for executives traveling by train to/from events who aren't entertaining other VIP's and deserve some quite space where they won't be bothered by paying customers. Unfortunately, time is money to most of us, so I suspect executives fly commercial when they have to travel for business.
9800 is an anomaly.... Without a theater rear window, it's useless for track or facilities inspection. It was made to be used as a chartered space that could be added to a scheduled train, and its only possible use in a business car fleet aside is to provide a larger meeting space. Had it been successful in revenue service, there would have been more cars built like 9800. But it wasn't. And there weren't.
Rather than keep a dedicated business car fleet, Amtrak might be better off chartering from one of the Class 1's or a private operator when the need arises.
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