I did this once with a book. It worked great. The small size was too small on the original file. I marked up all text, copied it to word, increased font size and changed the font and put it back on the reader. Then the font size small was ok to read.
When I get back tonight, I can take some screenshots of a novel in different sizes. I just found the test-document I made pretty good for comparison as everyone can resemble the document with a word processing program.
