anchor.diff:      %ChildrenPos = [SubtreePos|EntriesPos],
       ChildrenPos = SubtreePosList ++ EntriesPos,
       %ChildrenPos = [RootPos|SubtreePosList],
  +?debugVal(length(ChildrenPos)),
       if
       length(ChildrenPos) =< ?MAX_FILLED ->
           NewNode = {MergedMbr, ParentMeta, ChildrenPos},
  
positive.code:     {{_LeastMbr, LeastPos}, LeastRest} = least_expansion(
              Fd, SubtreeMbr, EntriesPos),
      LeastRestPos = [Pos || {Mbr, Pos} <- LeastRest],
      case insert_subtree(Fd, LeastPos, Subtree, Level, Depth+1) of
      {ok, NewMbr, NewPos, Inc} ->
          MergedMbr = vtree:merge_mbr(ParentMbr, NewMbr),
          NewNode = {MergedMbr, #node{type=inner}, [NewPos|LeastRestPos]},
          {ok, Pos} = couch_file:append_term(Fd, NewNode),
          {ok, NewMbr, Pos, Inc};
  
negative.code:     {ok, Result, NewHeight, _HeightDiff} = seedtree_write(
              Fd, Seedtree3, TargetTreeHeight - Seedtree3#seedtree_root.height),
  ?debugVal(Result),
  
      case length(Result) > ?MAX_FILLED of
          true -> ?debugMsg("WARNING! More nodes than allowed");
          false -> ?debugMsg("everything's OK")
      end,
  
      % NOTE vmx: I assume that the height can't change more than 1 level
      %     at a time, not really sure though
      % XXX vmx (2010-12-09): now we know the heihgt difference
  