Well, in this case the argument *does* evaluate to a string that is a
QName. It consequently matches the quoted description.

No, it evaluates to a nodeset with one node whose string value matches
QName. That is not the same as evaluating to a string.

Okay - "evaluation" is defined as what happens prior to any automatic
conversion that may apply. I lumped both together.

Is this interpretation of your words correct?

yes