http://musicbrainz.org/text.js is set by headers to not be cached. All of the scripts that use it, however, are. I'm guessing it's because text_strings.tt is in musicbrainz-server/root/scripts rather than musicbrainz-server/root/static/scripts. It's a small file, but it adds an extra get request to every single page. It would seem that the server could be configured to set caching for that file equivalent in expiration/etc to the scripts that use it, which would slightly improve page load times for every page on the site by eliminating 99.99% of those get requests.