Proposed resolution:

In [locale], paragraph 4, delete the parenthesized expression

(or, failing that, in the global locale)

In the overview of locale semantics, paragraph 4, is the sentence

If Facet is not present in a locale (or, failing that, in the global locale), it throws the standard exception bad_cast.

This is not supported by the definition of use_facet<>, and represents semantics from an old draft.