Excuse Me, but are UPPER CASE letters actually formatting that need be marked up...
...We have "BEEN THERE AND BACK AGAIN"
I suggest: http://tinyurl.com/3vozpku The practice of typography: modern methods of book composition By Theodore Low De Vinne, 1904 as a reminder that previous generations of authors, editors, and typesetters have all gone through these issues before, and had worked out among themselves what the minimal set of tools and markups were which were necessary to express the will of authors in a clear, clean and artistic manner. "We" have indeed been there before -- but it is not at all clear to me that the current generation of us "typesetters" creating e-books have nearly gotten "back there again." PS: Even in 1904 it was well recognized that there was lots of trash typesetting and book publishing "style" that one ought not feel obligated to emulate! Conversely what was good style in 1904 is still good style now.