You are confirming that layout page is the same thing as the page viewport. I believe that the layout viewport is also the same thing.
A screenshot would be helpful.
I would say that detail viewports are the views into the model from page layout (a.k.a. layout page; a.k.a. page viewport; a.k.a. layout viewport). I believe that detail viewports and details are the same things. I suggest that the word “page” should be expunged from Rhino documentation, unless it means physical piece of paper.
Ever since layouts were intoduced the term Page and Layout have been a cause for confusion. There was never a descision made what their definitive name is.
My take:
They are LayoutPages, problem solved.
A LayoutPage is what you get when you create a new layout. You see a white page with possibly a number of details on it.
That what displays that LayoutPage ( a 2D view that only pans and zooms) that window is the Page Viewport.
In short expunging Page is not going to happen.
Just always when reading Page or Layout either add Layout in front of Page or add Page after Layout.
@KelvinCLayoutPage is fine with me. If we always call it LayoutPage, we can call model viewports just viewports, and we can call detail viewports just details.
This Rhino documentation page: ( Viewport properties | Rhino 3-D modeling ) describes three kinds of Viewport Properties: Model viewport properties, Layout Viewport Properties, and Detail viewport properties. If we call model viewports just viewports, then we have to rename Viewport Properties. We can call them Space Properties: Model Space properties, Layout Space Properties, and Detail Space properties.
On Windows, layout is layout viewport. On Mac, there is a single layout viewport that contains all layouts (layout pages).
When we say viewports, it usually means model viewports.
When we say details, it usually means detail viewports.
Same with layouts and layout viewports.
In some cases, we ues model viewports, layout viewports, and detail viewports to reduce confusion.
That will be a huge change to documents (web pages, wiki, training guides, help topics…), command names, option names… It’s not likely going to happen.
I searched “page” in the whole Rhino help project. No more “page viewports”. All the other “pages” in layout related topics look fine to me. If you see any “page” that causes confusion, please let me know.