dc elements

In the process of incorporating the DC context set into the CQL document I 
have run across this question.

The DC context set 
(http://www.loc.gov/standards/sru/resources/dc-context-set.html) refers to
http://dublincore.org/documents/usageguide/elements.shtml   for semantics 
for the indexes.

However, that now has added several elements beyond the original 15:
it has added: audience, provinance, rightsHolder, instructionalMethod, 
accrualMethod, accrualPeriodicity, accrualPolicy

Should we revise the DC set to add these elements, or stick with the 15 and 
eliminate this reference?  My preference is the latter.

--Ray