anchor.diff:                                   EffectiveFr_L, HashCmpI, HashCmpL),
       NewState = State#rr_recon_state{struct = RTree, merkle_sync = SyncNew,
                                       stats = NStats},
  -    ?ALG_DEBUG("merkle (NI) - CurrentNodes: ~B~n  fail_rate(p1): ~p -> ~p",
  -               [length(RTree), PrevUsedFr, UsedFr]),
  +    ?ALG_DEBUG("merkle (NI) - fail_rate(p1): ~p -> ~p~n  NextNodes: ~B",
  +               [PrevUsedFr, UsedFr, NextLvlNodesAct]),
       send(DestReconPid, {?check_nodes_response, FlagsBin, MyMaxItemsCount}),
       
       if RTree =:= [] ->
  
positive.code:     MTSize = merkle_tree:size_detail(SyncStruct),
      Stats1 = rr_recon_stats:set([{tree_size, MTSize}], Stats),
      Stats2 = rr_recon_stats:inc([{build_time, BuildTime1 + BuildTime2}], Stats1),
      ?ALG_DEBUG("merkle (NI) - CurrentNodes: ~B~n"
                 "  Inner/Leaf/Items: ~p, EmptyLeaves: ~B",
                 [length(SyncStruct), MTSize,
                  length([ok || L <- merkle_tree:get_leaves(SyncStruct),
  
negative.code:                                  EffectiveFr_L, HashCmpI, HashCmpL),
      NewState = State#rr_recon_state{struct = RTree, merkle_sync = SyncNew,
                                      stats = NStats},
      ?ALG_DEBUG("merkle (I) - fail_rate(p1): ~p -> ~p~n  NextNodes: ~B",
                 [PrevUsedFr, UsedFr, NextLvlNodesAct]),
  
      if RTree =:= [] ->
             % start a (parallel) resolve (if items to resolve)
  