In the previous exercises, we discovered the importance of assessing the nature of the position, and of using our evaluation skills to back-up calculation (and vice-versa). We also learned that you can decide what to play just for purely psychological reasons.
In this exercise, we are going to taste the method of comparison. All my students got it right!
In the position above, White has basically to decide if he should capture the rook in a8 immediately, or if he should first move his knight, which is under attack. To add a little bit of spices to the position, Black threats to capture in e4 with a check, after which the a8 and d4 squares are both controlled.
If White captures immediately, 1.Nxa8 Qxe4+ 2.Qxa8 (2.Qxd4 is also possible) and then we have to decide where to move the knight, but even before that, we must give an evaluation.
If White starts with 1.Nf5+ Bxf5 2.exf5 Qxf5 3.Nxa8 Qe4+ 4.Be2 Qxa8, basically we get the same position without the Black’s bishop and White’s knight. Which one is better?
White is better in both cases, but there are several reasons why the second diagram is much better for White.
1) Parsimony. As in the first option, White does have to consider 2.Qxa8 and 2.Qxd4. The second option leaves Black with only one choice. There is less to calculate and the probability to make a mistake of calculation is lower.
2) Tempi. As in the first option, White’s knight is attacked and he has to spend a tempo to find a safe place.
3) Positional reasons. As in the first choice, Black remains with the bishop pair, and his white bishop is particularly important to control the white squares (e.g., d7-e6) in this pawn structure.
4) Black’s king is less safe in the second option, as he does not have the bishop to protect him.
After having compared these two options, I went for the second one. The game continued with 5.0-0 g6 6.Qa1! The pawn a6 is lost, the a-column will be open, and the Black’s king will be seriously endangered. I won a few moves later.
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