Deleting layouts is extremely slow. Rather than just deleting the layouts in question, Rhino changes the view on the screen with each deletion. Deleting, say 30, layouts is inordinately long. Therefore, I classify this as a bug.
Sometimes I see the layouts being deleted display. Sometimes I see model views being displayed before the detail is deleted.
My problem with terminology. I have edited the post to reflect the real problem.
When I delete multiple layouts, each layout is displayed before deleting. Often the main view is displayed in between. It also seems slower when multiple files are open.
Another observation. If you have two files open, delete layouts in the first, switch to the second file and delete layouts there, Rhino stops deleting layouts in the first file.
I am using that one file I sent with 33 layouts. I am trying ot split it into 33 separate files to fix the PDF problem. I open about 5 of the copies at a time. As soon as I start deleteng layout from a second file, the first stops deleting.