Pull a Page for Editing while scrolling through a whole file.
Sometimes while working on a multipage document I want to work on page while having to make references to other sections or looking back through the document to verify information, formatting choices, phrasing, etc. On a multi-monitor system, it would be nice to "grab" a page, pull it off to the side, and then continue editing the page while still scrolling through the larger document to find my various pieces of information.
This would be akin to working with a paper document where you pull a sheet out for editing / fact checking in a large document. Only with a computer, you can leave the sheet in place, edit the one on the side, and have access to the whole document too.