Dataflow in OWL-S

Hi,
I have a question regarding the representation of dataflow between two OWL-S
processes.  I've came across (probably in this same mailing list) the idea
of using <ParameterInst> construct to represent an instance of an output
which is used as an input to another process.  This is used in conjunction
with <TagBind> and <DataFlow> constructs.  For example:
 
    <dataflow:TagBind>
      <dataflow:tagBound>
        <dataflow:TagNames>
          <dataflow:tagName>step_0</dataflow:tagName>
        </dataflow:TagNames>
      </dataflow:tagBound>
      <process:Sequence rdf:ID="seq_1">
        <process:components rdf:parseType="Collection">
          <dataflow:Call>
            <dataflow:callee rdf:resource="#Login"/>
            <dataflow:tag>step_0</dataflow:tag>
          </dataflow:Call>
          <dataflow:Call>
            <dataflow:tag>step_0</dataflow:tag>
            <dataflow:callee rdf:resource="#DisplayUserProfile"/>
          </dataflow:Call>
        </process:components>
        <dataflow:flow>
          <dataflow:DataFlow>
            <dataflow:source>
              <dataflow:ParameterInst
                dataflow:i-or-o="&owls;out"
                dataflow:psParam="user_name" dataflow:psStep="step_0"/>
            </dataflow:source>
            <dataflow:destination>
              <dataflow:ParameterInst
                dataflow:i-or-o="&owls;in"
                dataflow:psParam="login_name" dataflow:psStep="step_0"/>
            </dataflow:destination>
          </dataflow:DataFlow>
        </dataflow:flow>
      </process:Sequence>
    </dataflow:TagBind>

My point is whether there is (or there will be in the future) an alternate
for this technique in SWRL or DRS.  SWRL enables to declare variables and it
seems also that in OWL-S 1.1 (specifically in the Process ontology) may be
ways to express such a dataflow using the "Binding", "theParam" and
"valueFrom" constructs.  However I haven't found any clear example of such a
solution.
 
Also, if the above system is to be kept, can the TagBind element be regarded
as a sub-class of "ControlConstruct"? My idea is that in a way, such a
mechanism is a means to express the flow control.
 
thanks
James