Has the US ever had anything like the compartment cars in Harry Potter? I think something like that could be really lucrative. It would be four seats, maybe as couches, in what would otherwise be a roomette. Perhaps a table could drop down like the top bunk. They could be great for business people trying to get work done on the train, people only going daylight on a long distance, or even people who want privacy to sleep, but not the whole first class experience. The fare would be structured to encourage multiple occupancy, like the sleepers.
To the best of my knowledge no. That's not saying something didn't exist at one point in time or another but to what I know there is nothing. I personally love what you are talking about which is basically the equivalent of the RZD Kupe.
I was not trying to fit anything in Viewliners per se. I was looking at a Venture car layout and trying to figure out how things would be. For rough estimation I just used 6' per, and the space that is removed from passenger compartment usage is what is not available on Venture cars due to the crumple zones (the vestibule area) at the two ends (which Viewliners and older cars do not have since they are not Tier III) and the huge ADA restroom taking out a hunk of space at one end. Ideally in an LD car in addition to the one ADA restroom there should be at least one more restroom IMHO for 40 odd passengers.
I was merely using the following diagram for back of the envelope scratching. Of course a more detailed analysis would yield slightly different results. And incidentally my analysis in the post that you quoted was wrong anyway as pointed out by cocojoyboy, which has been discussed further down thread.
Well even the old cars have some sort of a crash management system usually in the crash posts. My car had it's messed up by it's accident CN caused. And I'm the process of getting those back in order.
When we are talking about restrooms when you look at old passenger car designs the restrooms on coaches were roughly the same space. As shown in this diagram.
Now this is a New York Central car for the pre war James Whitcomb Riley (Chicago (Central Station)-Cincinnati. I wish it had better dimensions of the space on it but you can see what I'm talking about in terms of the large restrooms. Truthfully we only need one. So you are saving some space in on that side. And truthfully I think these restrooms are a bit too big. Interesting about this car it is a shorty by 5'3".
Personally I'm not a large fan of the two vestibule designs as I don't truthfully see much benefit to them, and I see better uses of space for that area. That's a great area to put your electric locker, storage closest, and anything else you might need for the operation of the car. I just think it's too much lost space. Now the 21 Roomette cars don't have a public restroom of any sorts as each car had their own direct dump back in the day. I believe when Amtrak did the converts on the final Heritage cars they used the room right next to the former community bathroom on the 10/6 which gave them an accessible space to use. And technically if I understand ADA properly you just need to have one handicapped space per car. Personally I would like to rewrite this a bit because it makes designs a bit more inflexible.
As far as a crumple zone I can't find what is the Tier III standard. But from what I'm saying is there is a lot of room to discuss all roomette cars, and I truthfully think they make a lot of sense now that we have a lot of single travelers again.
Now RZD has a different kind of new sleeping car that is rather unique being a tri level. The ADA room is on the main level (and it has a built in wheel chair lift in the vestibule), then two or three steps down to the lower level, and five steps up to the upper level. The aisles are on opposite sides of the car body on the various levels. Which is a great usage of space if you ask me.