Chess Strategy/Mobility

Mobility
Said the physician and chess master Siegbert Tarrasch, "Cramped positions bear the germs of defeat." Mobility and spatial advantages are key to a positional understanding of chess. A spatial advantage in a game will allow you to move your pieces from one edge of the board to the other faster than the opponent. In general, the side with a weak pawn or weak square to defend has a spatial disadvantage, as they may have to huddle their pieces together to defend that weak point. A spatial advantage allows you more territory to maneuver through. If your opponent has a spatial disadvantage, this is a long-term plus for you. The spatial advantage allows you to build up slowly, letting your opponent stew in his own juices for as long as you want him to. The advantage in space will not go away.

Playing with a spatial advantage
The principal idea of a spatial advantage is to not make too many exchanges. Think of a bottle of water. If you have a spatial disadvantage and your pieces are the water, the air is the remaining maneuvering space you have. But as the water is drunk (pieces get exchanged), there is more space for you, and material is still level!

The principle of two weaknesses
This is the rule that states that when a player has two separated weaknesses in his position, he is strategically lost. In the diagrammed position at right, White (Keres) has his pieces at their optimal posts. Every piece is pressuring a weak point in Black (Capablanca)'s position. The queen is especially well-posted; she is attacking both weak pawns at a6 and c6. Black's chances of surviving this game are pretty bad, but he can still struggle on. Therefore, White creates a third weakness and Black's position collapsed: '''22.Ne6! Qb8 23.Ng5! Rb7 24.Qg4 Bf4 25.Rc4 Rb5 26. Nxf7!!' White sacrifices his knight to create a kingside weakness, for after 26....Kxf7 27.Rd7+'' and White wins due to the weakness of the g7-pawn. Black declined the sacrifice with '''26....Re8! 27.g3 Qc8''', hoping to alleviate the pressure by making the transition into an endgame. However, Black's game is still lost due to the organic weaknesses on a6 and c6. '''28.Rxf4 Qxg4 29.Rxg4 Kxf7 30.Rd7+ Re7 31.Rxe7+ Kxe7 32. Bxg7.''' White is up two pawns and won on move 38.

In that position Black's pawns were already sufficiently protected, so White created a third weakness in the position and concentrated all of his efforts on it. This is another thing a spatial advantage provides: the ability to switch your troops between weaknesses quickly and effectively. Black's forces were tied up defending his weak pawns, and subsequently could not deal with White's kingside assault. Note also that due to the weaknesses on a6 and c6, Black is cramped due to the fact that these pawns will have trouble advancing to gain space. Also, Black could not move for losing the pawn.

Overextension
To be overextended means that you have more space than you can control. This can result in one of three things for your opponent:
 * 1. Receiving weak pawns as targets.
 * 2. Penetration into your camp.
 * 3. Outposts for his pieces.

Of course, none of these things are good. After exchanges, his pawns will be safe in his camp, while your pawns will be deep into his territory. This will allow him to easily line up pieces against them for target practice. Dr. Lasker said, "Distrust a pawn move; check carefully its balance sheet." What this means is that every pawn move weakens squares. So, after your pawns have advanced into enemy territory, many squares in your camp become weak. The opponent's rooks and queens can penetrate through open files into your position, and knights can take up "holes" that would be safely guarded by pawns, but are now weak because these guards have advanced.

One example of overextension in the opening is the Alekhine Defence, 1.e4 Nf6 2.e5 Nd5 3.d4 d6 4.c4 Nb6 5.f4, White hopes to prove that his pawn center gives him a spatial plus. Black hopes to refute this, saying that White's pawns are overextended and will become weak later in the game. The actual result depends on how both players play.

In this example at right, in the first diagram, White (Antoshin) has a huge space advantage. He can seek active play on either the kingside or the queenside. He will obviously be able to switch his pieces from wing to wing faster than Black, whose pieces are gridlocked on the back rank. However, Black (Ivkov)'s position has no defining weakness in it, yet there is a chance that White's pawns will become overextended. Antoshin here, rather recklessly, proceeds to expand in every direction possible. However, just like the Ottoman Empire of Turkey, he got overextended and his position collapsed only eight moves later! The game continued from here: 10.g4 g6 11.Bh6 Ng7 12.b4?! White's last move was questionable. Black can make some liberating moves here that will seriously expose White's weaknesses. 12....b6 13.Qd2 Nf6 14.Ke2? White's king will become a target for Black's pieces, which will penetrate through the soon-to-be-opened b-file. '''14....Kh8 15.Rag1 Bd7 16.Rg3 Qc7 17. Rhg1 b5!''' The second diagram has been reached. White has been slowly preparing for a kingside attack, since he correctly believes that his spatial advantage would not go away. However, he has left his queenside bare. Now his queenside caves in. 18.h4 bxc4 19.Bc2 cxb4 20.axb4 Rab8 21.h5 Rxb4 22.hxg6 fxg6 23.Rh1 Rb2 24.Kd1 Qa5 25.Ng5 Nxg4 26.Bxg7+ Kxg7 27.Rxh7+ Kg8 28.Qc1 Bxg5 29.Qxg5 Qa1+ 0-1. A drastic example of the risks of overextension. White ignored the fact that extra space could leave his position riddled with holes.