Using Qualified Names (QNames) as Identifiers in Content

One of the observations in section five (Namespace Bindings) asserts, as a
corollary to the principle of URI context-independence, that "QNames that appear
in an XPointer must not refer to in-scope namespaces".

One wonders why this corollary governs "QNames in XPointers" only. While certain
passages in the document do recognize alternatives to reified "in-scope
namespaces" with respect to attribute names and element identifiers, as a whole,
the finding ratifies - or at least tolerates - their reification as an
architectural feature, rather than isolating them as the transient artifact of a
particular processing model.

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