How to interpret PROV-XML's //prov:actedOnBehalfOf/prov:activity/@prov:ref

prov-wg,

I'm trying to decipher what the prov:activity element on a prov:actedOnBehalfOf element means in terms of PROV-O.


http://dvcs.w3.org/hg/prov/file/4f724446d633/examples/eg-40-xml-examples-by-term/xml/Delegation.xml
claims to be derived from example 37 of 
http://www.w3.org/TR/prov-dm/#anexample-wasAssociatedWith
and includes the XML fragment:

  <prov:actedOnBehalfOf>
    <prov:delegate prov:ref="ag1"/>
    <prov:responsible prov:ref="ag2"/>
    <prov:activity prov:ref="a"/>
    <prov:type xsi:type="xsd:QName">line-management</prov:type>
  </prov:actedOnBehalfOf>

but the DM example does not seem to include this kind of assertion.

Perhaps Delegation.xml should cite http://www.w3.org/TR/prov-dm/#term-delegation 's example 38?



Does the prov:activity element imply:

<ag1> prov:wasAssociatedWith <a> .

or, generally:

prov:delegate/@prov:ref prov:wasAssociatedWith prov:activity/@prov:ref .

If not, why is prov:activity permitted on prov:actedOnBehalfOf?

Thanks!
Tim