I think opps, that you have covered all one needs to know about the reasons for cross lining and they are clear and precise for anyone who needs to know.
I still paperhang a lot, as being from the slightly older generation, my clients still like wallpaper and with no disrespect for the younger decs out there, many do not know how to hang paper so either overprice a job so they don't get it, or do a site visit and disappear muttering the estimate will be in the post.
Now I do not ever claim to be a pro and I am willing to learn new ideas from others, but my years do give me an edge on having seen lots of products over those years. I have hung block printed papers where the colour washes off the pattern if you get it wet, material of 54" wide that has been paper backed for the walls and the client wanted it on the ceiling too!!
So, to come back to cross lining, we cross lined in the early days because the papers were very thick and much heavier than today. They would pull off lining paper if it was on the same plane so it was never done. ( Plus the paste was crap !!)
Later on, lining paper was made slightly wider, this was to help the increasing DIY market who wanted to hang newer and lighter papers themselves, but as many had no experience of how to cross line, they were hung in the normal way but being wider, the joins rarely matched.
PS. I also came across the stretched canvas with a plaster finish. I was working on properties in the 70's up in the West End around Marble Arch.
The timbers behind the canvas were quite often burnt black from the fires during the war and went in all directions with not one timber being the same length. The walls bounced if you hit them !
Sorry for rambling on, a little off post