[lelf]

> It may make sense to translate the same English sentence to something slightly different in different contexts in German

Then obviously you add context. It all has been solved for xx years http://www.gnu.org/software/gettext/manual/html_node/Context...

> JSLint/JSHint should be able to check for usages on an identifier like TITLE, PARAGRAPH_ABOUT_FOO, etc. easier than comparing strings (you'd have to build something custom for that)

That's not difficult if you absolutely need it

> Brevity. If you have the same long string of text written twice it may be useful to have a shorter identifier for it

You don't need them twice. Add attribute telling: this text can be translated. That's all.