Exchanging knight for bishop in the opening
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Hi,
There is often the opportunity to force exchange of knight for bishop in the opening, for example, my white knight moves to h4, attacking bishop on f5 or g6, when the bishop can't retreat to any safe squares. In the same way, as black, knight moves to a5 to attack bishop on c4 or b3.
I wonder whether I should usually take the opportunity to force this exchange? I understand the bishop is usually slightly superior to the knight, except in closed positions, and there is also the advantage of the bishop pair. Thanks for any advice.
A knight is worth 3.05 pawns, a bishop is worth 3.33 pawns.
See table 6 https://arxiv.org/pdf/2009.04374.pdf
A tempo is worth 0.33 pawns, as we know from gambits.
So if you spend 1 tempo Nf3-h4 to capture a bishop Nh4xg6, then you generally make about an even trade: you gain the bishop's pair, but you lose a tempo.
Nov 12, 2021
0
#3
tygxc wrote:
A knight is worth 3.05 pawns, a bishop is worth 3.33 pawns.
See table 6 https://arxiv.org/pdf/2009.04374.pdf
A tempo is worth 0.33 pawns, as we know from gambits.
So if you spend 1 tempo Nf3-h4 to capture a bishop Nh4xg6, then you generally make about an even trade: you gain the bishop's pair, but you lose a tempo.
Typically, though, it will cost you two tempi insted of one.
The Bishop moves once (Bc8-f5) and then gets axed.
The Knight moves three times (Ng1-f3-h4xf5) and then gets taken.
So you'll often end up trading (a Knight and three moves) for (a Bishop and one move).
#3
No: black has to recapture exf5 or hxg6 and that also costs a tempo.
Also useful to note: the value of a tempo decreases as the games goes on. In the early opening it is usually bad to chase a bishop with Na4/Nh4, but later in the game when all pieces are into play it is often worthwhile, why at that point the other side often spends a tempo to prevent it by making an escape hole for his bishop with ...a6 or ...h6.
Here is an example where black chases 2 Bc4 with 4...Ne5, but later has to regret the lost tempo
https://www.chessgames.com/perl/chessgame?gid=1001427
Here is an example where white chases 5...Bg6 with 7 Nf4. Note that loss of a tempo is worse for black than for white as white has a tempo more to start with.
https://www.chessgames.com/perl/chessgame?gid=1172189
Nov 12, 2021
0
#5
tygxc wrote:
#3
No: black has to recapture exf5 or hxg6 and that also costs a tempo.
Too dogmatic. The move hxg6 is only a loss of tempo if it doesn't improve Black's position.
If it activates the h8-Rook or increases Black's control of an important square then no tempo is lost by the move..
Here is another example where white chases the bishop
https://www.chessgames.com/perl/chessgame?gid=1918857
And here is a game where black prevents the exchange with 5...a6
https://www.chessgames.com/perl/chessgame?gid=1943566