Originally Posted by JSWolf
Not really. That option can add a lot of junk and change things. Not a good thing to do.
The best thing is to get familiar with HTML/CSS.
HTML/CSS yes, learning those are priorities for me now. As a new user I wanted a simpler way and thought I'd learn those later. That epub --> rtf --> docx --> odt --> epub conversion route produced pretty good results most of the time, if I were careful with search/replace in Word. It seemed docx stripped out a lot of rtf garbage, then odt stripped out a lot of docx garbage, then the final epub usually looked pretty clean at the book level. Even if the html were full of garbage, if the book looks clean to me as a new user not bothering with html at all, why should I notice or care? The main thing I wanted to accomplish was get rid of annoying header/footer/page# interrupting the flow, as opposed to building a perfect book.
Edit: And I haven't tested yet to see the results in quality of eliminating Word out of that and doing the search/replace and minor clean-up work in Open Office instead, to reduce conversions: epub --> rtf --> odt --> epub. The sequence with docx in it may be better than the sequence without docx.