I wonder what this layout would be.
1x1 lie-flat is essentially roomettes and can't achieve much more density and would likely be too expensive.
2x2 lie-flat requires some form of divider and crawling over someone else...that sounds very uncomfortable.
2x2 one atop the other on both sides of the train sounds reasonable.
2x2 lie-flat would actually take as much space as the roomettes, because they wouldn't be stacked vertically.2x2 one atop the other on both sides of the train *is* the roomette layout.
Every scenario I can see, Amtrak loses money by doing this. If you can fit the same number of seats in as an "all-roomette car", but you charge less, there's no financial benefit whatsoever.