I've posted a comparison between Sphinx and Dexy [1] - as well as
updated the phabricator ticket [2]. The tools are pretty similar in
what they can produce, so it really comes down to what people are
comfortable with. The learning curve for Dexy isn't steep, and I think
it's just enough easier to use compared to Sphinx for our purposes.
I wasn't able to find air-tight reasoning for one over the other for
qa-devel work - but found dexy a bit easier to use and template. Source
for both tutorials can be found on my bitbucket profile [3].
// Roshi
[1]
http://roshi.fedorapeople.org/comparing-dexy-and-sphinx.html
[2]
https://phab.qadevel.cloud.fedoraproject.org/T39
[3]
https://bitbucket.org/Rorosha/doc-tools