Automatically reference the resource instance referenced by an excerpt

If an author adds a quote in a resource document, the document's properties are automatically assumed as the defaults for the Quote Macro's parameters. But this automation is not provided for instances of the Excerpt Doctype, but should for convenience for the author.

Therefore: The Quote Macro within an excerpt should assume to default to the parent's resource document properties (or grand parent, if the excerpt is itself a child of another document type).