Originally Posted by Quiss
I'd like to add to the original question, if I may.
I noticed that, when opening an ePub that I converted with calibre, it opens broken down into individual files corresponding to each chapter, so I guess it was split whenever there was an H2 tag.
However, when I save the original HTM (filtered) file in Word and then open in Sigil for editing, I get only one file.
Does this matter in any way? Can I just leave it as one file? (I haven't added the cover yet)
It matters to some devices if your file (inside the EPUB is bigger than 260K) (calibre has various rules it can/will invoke to break files)
There are many MR threads discussing file size and reflow performance
K.I.S.S. Keep It Small (and) Simple
Except for possibly doing 'edits', I can't see any any advantage for a single, huge file