code: public static Pattern controlsStateChangeButIsParticipant()
  	{
  		Pattern p = new Pattern(SequenceEntityReference.class, "controller ER");
  		p.add(linkedER(true), "controller ER", "controller generic ER");
  		p.add(erToPE(), "controller generic ER", "controller simple PE");
  		p.add(linkToComplex(), "controller simple PE", "controller PE");
  		p.add(participatesInConv(), "controller PE", "Conversion");
  		p.add(left(), "Conversion", "controller PE");
  		p.add(right(), "Conversion", "controller PE");
  		// The controller ER is not associated with the Conversion in another way.
  		p.add(new NOT(new InterToPartER(1)), "Conversion", "controller PE", "controller ER");
  
  		stateChange(p, null);
  
  		p.add(equal(false), "controller ER", "changed ER");
  		p.add(equal(false), "controller PE", "input PE");
  		p.add(equal(false), "controller PE", "output PE");
  
  		return p;
  	}
docs: Pattern for a EntityReference has a member PhysicalEntity that is controlling a state change
  reaction of another EntityReference. This pattern is different from the original
  controls-state-change. The controller in this case is not modeled as a controller, but as a
  participant of the conversion, and it is at both sides.
  @return the pattern