How should EPUB flow layout work?
I understand the idea in principle: if we have a small display and/or poor eyesight, then we need the same text but less on each page. This is reflowable layout, and it works well for pure text documents such as novels. Other objects such equations, images, diagrams, or tables are harder but they usually fit into rectangles. I would expect these to resize to fit in the new page size. Text items such as tables and equations might scale as text, while images might scale as the page width. We cannot move objects past the text, as the text may refer to 'the diagram above' or something like that. But anything extra we can do to preserve the look, such as flowing text, is a bonus.
I have a large technical document. It has diagrams and equations but I do not was text. It largly works as an EPUB. When something is broken it is usually obvious ( e.g. bug 138043 ). However, sometimes a table is split in silly ways with the header on one page and the rest on the next; or a particular image comes out smaller than others that were the same size. I cannot file a bug because I do not know it is broken: it may look a bit odd but the EPUB layout might be doing the right thing for a perfectly good reason.
If I knew what the EPUB flow layout wanted, I might be able to lay out my document slightly differently. A good explanation in the documentation might help others get good results too.