I remember using reveal codes in WP back in the day. Now I just use LaTeX ;)
I imagine this could be one reason why few people want reveal codes in word processors any more. Those who like to think in code will use LaTeX and other markup systems. (Thus enabling things like generating reports from simulation runs, which is hard to imagine if you are stuck with a word processor.) There are intermediate solutions like LyX, which is a GUI frontend to LaTeX, but as such it is not comparable to what we call word processors.