anchor.diff:      %insert_subtree(Fd, RootPos, Subtree, Level, 0),
       case insert_subtree(Fd, RootPos, Subtree, Level, 0) of
       {splitted, NodeMbr, {Node1Mbr, NodePos1}, {Node2Mbr, NodePos2}, Inc} ->
  +?debugMsg("splitted"),
           Parent = {NodeMbr, #node{type=inner}, [NodePos1, NodePos2]},
           {ok, Pos} = couch_file:append_term(Fd, Parent),
           {ok, NodeMbr, Pos, Inc+1};
       {ok, NewMbr, NewPos, Inc} ->
  +?debugMsg("as is"),
           {ok, NewMbr, NewPos, Inc}
       end.
   
  
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:         LeastRestPos = [Pos || {Mbr, Pos} <- LeastRest],
          if
          % Both nodes of the split fit in the current inner node
          %length(EntriesPos)+2 =< ?MAX_FILLED ->
          length(LeastRestPos)+2 =< ?MAX_FILLED ->
              ChildrenPos = [ChildPos1, ChildPos2] ++ LeastRestPos,
              NewNode = {MergedMbr, #node{type=inner}, ChildrenPos},
              {ok, Pos} = couch_file:append_term(Fd, NewNode),
  