Let's say for a given <dataschema> that one of the <attribute> stanza attributes is 'category'. Within that given <dataschema>, all 'category' names are unique. Some of those 'category' names, however, will appear in other <dataschema> stanza's 'category' names.
Does that make sense? Does that change the code at all? Have I made you so dizzy that you can't get off the floor?