The definition of Bib-1 Use Attribute Any says ".... the set of records selected is the union of the sets of records selected by each of the (appropriate) Use attributes that the target supports." How does this apply across operands?

For example, consider an Any search for "'children' AND 'art'", i.e.:

(use:any; Term:children) AND (use:any; Term:art)

Would this locate only those records where both "children" and "art" occur for the same use attribute? Assume Use attributes Subject and Title are supported. Would this search locate a record with subject "children in art", but not a record with title "Activities for Children" and subject "Art"?

No, that would not be the correct behavior; the search should not exclude the latter record (with title "Activities for Children" and subject "Art". ) The defintion of "Any" applies to a single operand, not across operands. Thus for the example search the two operands would be evaluated independently; the latter record would qualify for both operands and should be selected.