Issue 12055 Map referencing behaviors

This is in reference to the proposal posted here:
http://www.oasis-open.org/committees/download.php/24910/IssueNumber12055.html

As noted at Tuesday's meeting, there has been some discussion off the list
about this item, primarily related to default behaviors. This proposal
states that the described behaviors (such as that for cascading metadata)
may change in a given specialization. For example, in the general topicref
case and in most specializations, metadata specified within the