I know I'm not the guy writing the language code, but it seems like it would make more sense to me to have en-GB fall back to en-US and vice versa, than do what's being done now. (Especially considering that en-US doesn't exist in vanilla)
But I suppose most modders were slacking off on including English text in their language sets, not American text. Even so, it's an odd special case where American English speakers have to debug their mods a little differently from people who speak, say, French. Ah well, if it bothers you that much, fork a new executable as a proof of concept or something. Doesn't bother me that much.
