[neild]

Much more prosaic (if slightly embarrassing), I'm afraid: The update was non-trivial (this CL is simple, but there are some accompanying ones in x/text which are not) and it didn't hit the top of the priority list for anyone who understands x/text.

Go is pretty much entirely developed in public; there are some Google-internal customizations but none of them are particularly exciting and almost all changes start in the open source repo and are imported from there.