Is the choice element in Policy correct

To TC:

    

    We have been looking at the xsd for Policy and there is a central

    "choice" element that does not appear correct, although for

    mainstream Policies it probably does not show up.

    

    The choice element is the following:

     2028

      <xs:choice maxOccurs="unbounded">

          <xs:element ref="xacml:CombinerParameters"
      minOccurs="0"/>

          <xs:element ref="xacml:RuleCombinerParameters"
      minOccurs="0"/>

          <xs:element ref="xacml:VariableDefinition"/>

          <xs:element ref="xacml:Rule"/>

      </xs:choice>

    
    This is the construct that allows multiple Rules in a Policy, which,
    looking at

    the Rule element alone, seems ok, as default is minOccurs="1", and
    it

    inherits maxOccurs="unbounded" from the choice element itself.

    

    However, very little else about this element appears to make sense:

    
      
Since this is a choice element, w minOccurs="1", one could
        choose any

        of the other 3 elements and nothing else, and the result would
        be a

        Policy with zero Rules. Does this make sense?

      
With zero Rules, even if you used the Policy to define
        VariableDefinitions,

        they cannot be referenced outside the Policy, and since there
        are no

        Rules in the Policy, there is nothing that would ever use the

        VariableDefinitions.

      
Does it make sense to have multiple instances of either
        CombinerParameters

        or RuleCombinerParameters? i.e. can't all the parameters be put
        in one

        element in both cases? If not then why are these elements in the
        choice

        block that allows unbounded instances?

    
    Please advise as to whether the above interpretation is accurate. If
    so, we would

    like to consider raising this as an issue for action.

    

        Thanks,

        Rich