> Now I want to find all of the people in <project_staff_roles> who are 
> listed more than, arbitrarily, 5 times.

<xsl:key name="p" match="project_staff_role"  use="@staff_id"/>
....


<xsl:for-each
select="project_staff_roles/project_staff[generate-id()=generate-id(key('p',@staff_id)[6])">

David

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