Interesting... For some reason, I thought \ttfamily was also hyphenated
except when in \verb. I suppose the "canonical" way in fontspec is to
set HyphenChar to None. But I think I'd like \ttfamily to be hyphenated,
so maybe setting \verbatim@font following your answer in
<http://tex.stackexchange.com/a/91308/117845> is what would work best
for me:
\makeatletter
\newlanguage\no@hy
\renewcommand*\verbatim@font{\ttfamily\language=\no@hy}
\makeatother
Should we file a bug in fontspec so that HyphenChar=None is the default
setting in \setmonofont?
Isaac