The KP Nimzovich Defence, also known as the Nimzo-Indian Defence, is a popular chess opening that arises after the moves 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4. It is named after the Latvian-Danish chess player Aron Nimzowitsch, who was one of the leading chess players in the world in the 1920s and 1930s.
The Nimzo-Indian Defence is a hybrid opening that combines elements of the Queen's Indian Defence and the Bogo-Indian Defence. The main idea behind the Nimzo-Indian is to put pressure on White's center pawns with the bishop on b4, while also preparing to develop the rest of the pieces. Black's goal is to restrain White's central pawn majority and create imbalances that can be exploited later in the game.
Here are some reasons why to play the Nimzo-Indian Defence:
1. Solid structure: The Nimzo-Indian is a solid opening that gives Black a good pawn structure and piece development. It is difficult for White to create weaknesses in Black's position.
2. Flexibility: The Nimzo-Indian offers Black a lot of flexibility in terms of piece development and pawn structure. Black can choose to play with or without the c5-pawn advance, and can develop the knight to d7, e4, or c6, depending on the situation.
3. Control of key squares: The bishop on b4 controls the important e4-square, which can be a powerful outpost for a knight. The bishop also puts pressure on the c3-knight, which can be a target for Black's pieces.
4. Active piece play: The Nimzo-Indian often leads to positions where Black's pieces are actively placed and ready to create threats. The bishop on b4 can be redeployed to a more active square, such as d6 or c5, and the knight on f6 can jump to e4 or d5, putting pressure on White's position.
However, there are also some potential downsides to playing the Nimzo-Indian Defence:
1. White's space advantage: White often gains a space advantage in the center, which can be used to launch an attack on the kingside or to create a passed pawn on the queenside.
2. Doubled pawns: If White plays a3 to force the exchange of the bishop on b4, Black will end up with doubled pawns on the c-file. These doubled pawns can be a long-term weakness in the endgame.
3. Complexity: The Nimzo-Indian is a complex opening with many different variations and sub-variations. It requires a lot of study and preparation to play it well.
4. Risk of overextension: Black needs to be careful not to overextend in the Nimzo-Indian. If Black plays too aggressively, White can often launch a counterattack that exploits Black's weaknesses.
In conclusion, the Nimzo-Indian Defence is a solid and flexible opening that offers Black good chances to fight for the initiative. It requires a lot of study and preparation, but can be a powerful weapon in the right hands. However, it also has some potential downsides, such as White's space advantage and the risk of overextension. Ultimately, whether or not to play the Nimzo-Indian Defence depends on your personal playing style and preferences.