code: public Operation getSimplifiedJoinOp(Mapper mapper, List parentList)
      {
          int maxSimplifiedIn = DeepRelationshipUtility.MAX_SIMPLIFIED_IN;
          boolean differentPersisterThanParent = differentPersisterIdThanParent(mapper);
          if (differentPersisterThanParent)
          {
              maxSimplifiedIn = Integer.MAX_VALUE;
          }
          return mapper.getSimplifiedJoinOp(parentList, maxSimplifiedIn, this, differentPersisterThanParent);
      }
docs: mapper is not necessarily this.relatedFinder.mapper. chained mapper