That makes perfect sense. It did seem like a wacky mix of combined trains that just couldn't possibly be efficient. So with that in context, it would seem that a dedicated, specific train from LA to Las Vegas could be done efficiently and could retain a huge demand. Well, until the passengers lose all their money on the slots...Budget cuts indirectly. The reason these trains offs happened was primarily because inadequate number of Superliners were ordered to run everything after the Hi-Levels were taken off line. It was lack of equipment that did these trains in. These were never mandated trains as part of the original system. They were added by Amtrak as experimental service and lived as long as they could. Just before their discontinuance the entire CZ/DW/Pioneer mix was a mess, with each train running some set number of days a week, and none daily west of Salt Lake City. Discontinuance made it possible to restore all remaining services to daily AFAIR.
Honestly, most major cities in the West that were abandoned when the Desert Wind/Pioneer were discontinued are still serviced by SOME service, except Las Vegas and Boise, ID. The LV link is important, albiet not looking like it would be a part of the Amtrak network. Boise would be the largest city in the West previously served that would remain without rail service.