code: void iteratorSpecialDelete(
                                Iterator       iter,
                                GBSNode        node,
                                int            index)
      {
          _vno++;
          if ((_vno&1) == 1)
          {
              node.deleteByLeftShift(index);
              node.adjustMedian();
              _population--;
          }
          synchronized(iter)
          {
          }
          _vno++;
      }
docs: Allow an Iterator to delete an item by direct removal from a single
  node.
  
  <p>The Iterator has determined that the item to be deleted resides
  in a leaf node with more than one item in the node.  Removal of the
  item from the leaf can be done without further modification to the
  tree.  The Iterator has already synchronized on the index.</p>
  
  @param iter The Iterator itself which is used as the
  synchronization target for a void synchronization
  block.
  @param node The node from which to delete.
  @param index The index within the node of the item to delete.