Cache fixes

Fixes bugs, including fixes removed from NetworkAtomics (whoops). See individual commit messages.
There's a missing word or phrase, or something else wrong with this sentence: "... in order to correctly single-locale compilation ..." doesn't scan. And it's not really compilation we're talking about here, it's the (style of) code generated during single-locale (comm=none) compilation, right? It would be good to clarify that.