I am typesetting a novel which in a few places contains very long strings of capital letters split into shorter groups separated by hyphens, something like SIERRA-TANGO-CHARLIE-ECHO-YANKEE-OSCAR-MIKE-NOVEMBER-CHARLIE-VICTOR-WHISKEY-ALPHA-PAPA-BRAVO-UNIFORM. Wherever such a 'word' appears, the TeX engine has a hard time trying to typeset it without having it fall off the page margin and spewing pages of 'Overfull \hbox' warnings (as if LaTeX didn't emit too much unnecessary output already).
Begrudgingly, I have added
\- sequences to the strings, which helped TeX find better word breaks (I'd prefer to put hyphenation information somewhere where it wouldn't be distracting, but
\hyphenation doesn't seem to support specifying word breaks for hyphenated words). I have also adjusted
\fontdimen settings, and it helped in some cases, but there still remain instances where such 'words' begin a paragraph and
\fontdimen makes no difference, like
``SIERRA-TANGO-CHARLIE-ECHO-YANKEE-OSCAR-MIKE-NOVEMBER-CHARLIE-VICTOR-WHISKEY-ALPHA-PAPA-BRAVO-UNIFORM-BLAH-BLAH-BLAH-BLAH-BLAH-BLAH'', Tom said.
Sometimes the overflow can be as small as a single hyphen; I tried to adjust
microtype's character protrusion settings to mitigate these cases, but I failed to make it do anything. Setting
\emergencystretch produces underflows instead, and still looks quite ugly.
What else can I do to remedy this?
I am currently using XeLaTeX, and would prefer not to change the engine; I really need the bidirectional capabilities of XeTeX, and I find the time it takes to run LuaLaTeX unacceptably slow.