[owl-s] using disjointWith for IOPEs

 I have some issues about the use of "disjointWith" for the IOPEs classes with the structure in OWL-S 1.0.  

IOPE structure:
 * class Parameter 
 	- properties:
    - parameterType 
 	- subclasses:
 		    - Input
 		    -ConditionalOutput
 		    	-properties: coCondition (ranges Condition)
 			        - subclass: UnConditionalOutput (maxCard=0 on coCondition)
 *class Precondition
 	    - properties:
 		    - preCondition(ranges Condition)
 	
 *class ConditionalEffect	
 	     - properties
 	 	    - ceCondition(ranges Condition)

Monika: Over here there is another property that should be added, since it is defined in the Ontology, 

ceEffect(ranges Condition - as defined in the Process.owl)

David & All, Are we sure that the range of ceEffect is a Condition?, I am confused [This can be the subject of another email, however I am still adding it here ]

       - subclass: UnConditionalEffect (maxCard=0 on ceCondition)
 	
 * IOPE's are disjoint
 

The question that bothers me, is under what conditions should one declare a class as disjoint with another class. In OWL there is nothing that restricts the use of disjointWith i.e any class can be declared disjointWith any other, although they may not really related in anyway!!!!. However, I believe classes should be declared disjoint , whenever there are chances of them being used interchangeably otherwise it leads to redundant declarations. 

In case of IOPEs, for 1.0, for e.g, we have Parameter as a superclass of both Input and ConditionalOutput. Precondition and ConditionalEffect are independent entities. 

I am confused by the following

- <rdf:Description rdf:about="#Input">
  <owl:disjointWith rdf:resource="#ConditionalOutput" /> 
  <owl:disjointWith rdf:resource="#Precondition" /> 
  <owl:disjointWith rdf:resource="#ConditionalEffect" /> 
  </rdf:Description>

I can understand Input being disjointWith ConditionalOutput, however I am confused by the last two disjointWith declarations. I believe the semantics of P and CE make them anyways disjoint from I and O. What are the chances that their instances would be used interchangeably for Input, since they do not have anything in common: subclass, domain or  range. I do not understand, why they should be a part of the disjointWith declarations for Input. Had they all been subclass of a common class say for e.g "Parameter" then it would make sense. I agree that there is nothing that stops me from declaring them as disjointWith, however I wonder about the utility of such a declaration. 

I have a similar problem with 

- <rdf:Description rdf:about="#ConditionalOutput">
  <owl:disjointWith rdf:resource="#Precondition" /> 
  <owl:disjointWith rdf:resource="#ConditionalEffect" /> 
  </rdf:Description>

- <rdf:Description rdf:about="#Precondition">
  <owl:disjointWith rdf:resource="#ConditionalEffect" /> 
  </rdf:Description>

Maybe, I do not understand the semantics of disjointWith. Please help 

Thanks,

Monika