Grandmaster plan in N vs B endgame

This nice endgame was played some days ago in Bundesliga.

() vs. ()
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[Event "Bundesliga"] [Site "Germany"] [Date "2010.10.10"] [Round "2.1"] [White "Postny, Evgeny"] [Black "Sandipan, Chanda"] [Result "0-1"] [WhiteElo "2595"] [BlackElo "2641"] [Annotator "SR"] [SetUp "1"] [FEN "3n4/pp5p/2p2k2/5p1P/1PP1p2p/2P1P2P/4BP2/2K5 w - - 0 25"] [PlyCount "36"] [EventDate "2010.??.??"] {How would you assess this endgame?} 25. c5 { this looks logical to free the bishop's way} (25. f4 $1 exf3 { to get e5 and g5 for the knight} 26. Bxf3 { maybe with the pressure on c6/b7 white could save the game?} Nf7 27. Kd2 Ng5 { black has to pressurize h3 or white will save the game!} (27... Ne5 $2 28. Be2 Kg5 {black is better : space advantage and white's king has problems to become active. And h3 and h5 are weak, despite being on white squares.} 29. c5 { and here black has to find} h6 $1 (29... f4 $2 30. h6 $1 { saves the game thanks to the clever idea Bd1-c2} (30. exf4+ Kxf4 31. c4 h6 32. b5 Nd7 33. Kc3 Nxc5 34. Kb4 Ne4 35. bxc6 bxc6 36. c5 Nf2 37. Bf1 Kg3 $19) 30... Kf5 (30... f3 31. Bd1 Nc4+ 32. Ke1 {only move} Nxe3 33. Bxf3 Kf4 34. Be2 Nf5 35. Bg4 Ne7 36. Kf2 Kg5 37. Ke3 Kxh6 38. Kf4 $11 { and with an alive King and b7/c6 on white, white is ok}) 31. exf4 Kxf4 32. Bd1 Nf3+ 33. Kd3 Kg3 34. Ke3 Ng5 35. Bc2 Kxh3 36. Kf4 Nf7 37. b5 $1 Kg2 (37... Nxh6 38. bxc6 bxc6 39. Be4 Kh2 40. Kg5 Nf7+ 41. Kxh4 Nd8 42. Bxh7 a5 43. Bc2 $11) 38. Bxh7 Nxh6 39. bxc6 bxc6 40. Be4+ Kg1 41. Bxc6 h3 42. Bd5 h2 43. c6 Nf7 44. c7 Nd6 45. Ke5 Nc8 46. Kd4 $11 (46. Ke6 $4 a5 $19)) 30. Bd1 (30. c4 f4 31. exf4+ Kxf4 32. Kc3 Kg3 $19) 30... Kf6 31. Be2 Nf7 { back to the good g5 square! So it was stupid to play Ne5.} 32. Bf1 Ke5 33. Ke2 Ng5 34. Bg2 f4 35. c4 Kf5 36. exf4 Kxf4 37. b5 Ne6 38. bxc6 bxc6 39. Kd3 Nxc5+ 40. Kc3 a5 41. Bxc6 Kg3 $19) 28. Bg2 Ke5 { better King, pressure on h3, it's winning, if black plays carefully} 29. Ke2 f4 (29... b6 {is less natural} 30. Bxc6 Nxh3 31. Kf3 h6 32. Kg2 Ng5 33. Ba4 Ne4 34. Kh3 Nxc3 35. Bb3 Ke4 (35... a5 $2 36. c5 $1 {only move} a4 37. cxb6 Kd6 38. Be6 Nd1 39. Kxh4 Kc6 40. Kg3 Kxb6 41. Kf4 a3 42. Kxf5 Nxe3+ 43. Kg6 Kb5 { threatening Nc4} 44. Bb3 $11) 36. Bc2+ Kxe3 37. Bxf5 Kd4 38. Be6 b5 39. cxb5 Nxb5 40. Kxh4 Kc3 41. Kg4 Kxb4 42. Bg8 Nd4 43. Kf4 a5 $19) 30. c5 (30. b5 $2 { gives black a free a-passed pawn} f3+ $1 31. Bxf3 Nxf3 32. Kxf3 a5 $19) 30... Kf5 {white will very soon be in some zugzwang} 31. exf4 Kxf4 32. b5 (32. h6 Kg3 33. Kf1 Nf3 34. Bh1 Kf4 35. Kf2 Ng5 36. Bg2 Ne4+ 37. Ke1 Nxc3 38. Bf1 Nd5 39. b5 cxb5 40. Bxb5 Nf6 $19) 32... Ne4 33. bxc6 bxc6 34. Kd3 (34. c4 a5 35. Kd3 a4 36. Kc2 Nxc5 37. Kb2 Kg3 38. Bxc6 Kxh3 39. Ka3 Kg4 40. Kb4 h3 $19) 34... Nxc5+ 35. Kc4 Ne4 36. h6 a5 37. Kb3 c5 38. Ka4 Nxc3+ 39. Kxa5 Ne4 40. Kb5 Nf2 41. Kxc5 Kg3 42. Bf1 Nxh3 $19) 25... Nf7 26. Kd2 Ng5 27. Bf1 Ke5 { black is on top. More space, better King and pressure on h3.} 28. Kc2 f4 29. Kd1 f3 $1 {taking more and more space! It's very difficult for the computer to find a winning plan! Could you?} (29... fxe3 30. fxe3 { and black will win h5 but it's not easy to win the game}) 30. Kd2 h6 { the first step is to grab h5, this will allow to play h6-h5} 31. Kc2 Nh7 { now h3 is not attacked any more but the white bishop can't take benefit of that } 32. Kd2 Nf6 33. Bc4 Nxh5 34. Bf7 {would have the bishop been able to reach c8, of course it wouldn't be the same story} Nf6 35. Bc4 (35. Bg6 $5 { could almost have saved the game!} a5 $1 {another black's idea} (35... Ng4 { a very important idea, coming again and again in this endgame} 36. Ke1 a5 37. bxa5 Nf6 38. Kd2 Nd7 39. Bf7 Nxc5 40. Bc4 $13 { to stop Nd3. I'm not sure black can win now}) 36. bxa5 Nd7 37. Be8 Nxc5 38. c4 {white may feel out of danger but black is able to win} Kd6 39. Bg6 Kc7 40. Bf5 (40. Bh5 Nd3 41. Bxf3 Nxf2 42. Ke2 Nxh3 43. Bxe4 Ng5 44. Bd3 Kd6 45. Bf5 Ne6 46. Kf3 Nc5 47. Bc8 Kc7 48. Bf5 Nb3 $19 49. Kg4 Nxa5 50. Bd3 Kd6 51. Kxh4 Kc5 52. Kh5 Nxc4 53. e4 Kd4 54. Be2 b5 55. Kxh6 b4 56. Bd1 Ne3 57. Ba4 c5 $19) 40... Kb8 41. Kc3 Nd3 42. Bxe4 Nxf2 43. Bxf3 Nxh3 44. Kd4 Ng5 45. Bh1 Ka7 46. e4 Ka6 47. Kc5 Kxa5 48. e5 h3 49. Kd6 Kb4 50. e6 Nxe6 51. Kxe6 Kxc4 52. Kf5 h2 53. Kg4 Kd3 54. Kg3 c5 55. Bxb7 c4 56. Kxh2 c3 57. Bc8 Ke4 $19) 35... Nh7 $19 { going back to g5} ({or} 35... Ng4 36. Ke1 Kf6 37. Bf1 Kf5 38. Bc4 Ne5 39. Bf1 h5 {will allow Ng4 for ever} 40. Kd2 Ke6 41. c4 Ng4 $1 42. Ke1 Nh2 $19 43. b5 Ke5 $19 {zugzwang}) 36. Kd1 Ng5 37. Bf1 Kd5 { stopping all Bc4. Now the last step: h5 and Ng4 are unstoppable} 38. Kd2 (38. Kc2 Nf7 39. Kb3 Ne5 40. Kc2 (40. c4+ Ke6 41. Kc3 Kf5 42. Kd4 h5 43. b5 Ng4 $19) 40... h5 41. Kd2 Ng4 42. Ke1 Nh2 $19 {with zugzwang to come}) 38... Nf7 39. c4+ (39. Kc2 Ne5 40. Kb3 h5 41. c4+ Ke6 42. b5 Ng4 $19) 39... Ke5 40. Kc3 h5 41. Kd2 Nh6 42. Ke1 Ng4 {with total domination and zugzwang!} 0-1