Many years ago I wrote a Novice Nook column, "The Fun of Pros and Cons." This column was directed at the many players who play way too fast in long time-control games. The column and its sequel "Chess is Decisions" have proven very helpful as reference material for my students in need of a brake.
I tried to convince them that not only could they play better if they slowed down, but that taking time to decide between various candidate moves is not only necessary for higher level play, but doing so could even be fun.
The basic idea is to select candidate moves and then, if possible, assume the opponent will make best moves and analyze ahead to a quiescent position to be evaluated. If the positions are evaluated as "close" (i.e. none wins or loses material or gets checkmated), use your positional judgment to decide which position you would rather play, and thus which move you would like to make.
Very often, in comparing candidate moves (and thus their possible positions), there are "pros" and "cons" of achieving one position over the other. Many low-rated players make these decisions superficially, often without any analysis. If their "guess" is correct then they make a good move, but if not...
So let's start with a simple example:
After 6.Bxc6+ Black has two ways to recapture, 6...bxc6 and 6...Qxc6. Clearly neither wins or loses the game outright, so there is a choice that may make a difference.
When I review time-stamped games with weaker players in similar positions, they often pick a re-capture immediately. When I ask why they played the move they did, say 6...Qxc6, and why so quickly, they may answer something like "I did not want to double my pawns" or "I did not want to isolate my a-pawn.
If you are playing a speed game or you are an extremely strong player, this type of reasoning my suffice. After all, in a speed game, there's not much time to weigh factors and if you are a very strong player, you know which factors to weigh and about how much weight to give them. Unfortunately, these are much weaker players and it occurs in a long time-control game which just started, which means they had plenty of time to weigh the pros and cons.
Maybe they would even learn something along the way. Let's take a look at the possible ideas that Black could have with either recapture, and list some pros and cons we could use for comparison.
Often the pros for one move are the cons for some of the others, and vice versa:
If Black plays 6...Qxc6
- There are no doubled or isolated pawns.
- The queen is now on the color of the traded bishop, so no bishop can attack it (or pin it to the king!).
- If Black later plays ...cxd4 then after cxd4 Black's queen will be on an open file, and vulnerable to a rook attack.
- The number of pawns in the center are equal, so after ...cxd4 cxd4 Black will only be able to attack the d-pawn with pieces, and
- The queen is no longer attacking d4.
If Black plays 6...bxc6
- Black will have a semi-open b-file and White will have no semi-open or open files
- Removing the b-pawn from b7 allows the bishop to develop on the a6-c8 diagonal. In particular, with the white bishop gone, Ba6 may make it difficult for White to castle kingside.
- With an extra pawn in the middle, Black can play a later ...cxd4 and after cxd4 break a second time with ...c6-c5 and White's center will crumble, as the pawn on e5 will lose its main protector.
- The black queen is still attacking d4.
- The a-pawn becomes isolated
- The c-pawns are doubled but, because the white d-pawn is fixed, there is no way White can prevent Black from undoubling them with ...cxd4. So this is technically not a con although many lower-rated players use this as their sole decision criteria!
I gave this position to Stockfish 7 and, after 30 ply, it rates 6...bxc6 at -0.7 (Black much better and almost winning due to White's mistakes 5.Bb5 and 6.Bxc6+) and 6...Qxc6 at only -0.2 (Black is slightly better). So the "automatic" capture with the queen is actually a fairly big mistake. But the bigger mistake would be to not give it much thought and just move quickly. In a game at 40 moves in 2 hours (3 minutes per move), thinking about such a move for 10 minutes would be way overkill, but moving in five seconds grave underkill.
Like most things, there is a happy medium and, assuming you don't already know that 6...bxc6 is clearly superior, giving it 60-120 seconds thought would be quite reasonable, even if you come to the wrong conclusion -- that's how you learn.
Let's take another "multiple choice" decision:
Black has just captured a piece on g3. What should White play?
If you don't think he should recapture, perhaps this puzzle wasn't for you. So the choice is between 1.fxg3, 1.hxg3, and 1.Nxg3. Not surprisingly, this is a closer decision than our first example.
1.Nxg3 is the only move that leaves the pawn structure intact and does not double any pawns. Not surprisingly, many lower-rated players might make this move immediately (and, unlike the first example, their move, if not their time management, would be reasonable).
1.fxg3 semi-opens the f-file for the white rook. This is OK for the rook, but with the reduced material on the board there is basically no chance that White can attack along that file and there are no great entry points into Black's position. Also, the rook already has semi-open files on the queenside to attack the potentially strong black pawns on the a- and b-files. Moreover, the pawn mess on g3/g2/h2 is very weak and not worth anywhere near three pawns.
1.hxg3 retains one "pawn island" and follows the principle "recapture toward the center." Of course, this principle is not always necessary if there is a piece capture, too, as there is here. Further, as GM Larry Kaufman has written, a rook's pawn is weaker than the other pawns because it only attacks one square, so moving the h-pawn to the g-file may block the g2 pawn, but it makes the pawn on g3 stronger than it was on h2. 1.hxg3 also leaves the knight closer to the queenside where the action may soon be, but that's a fairly minor consideration.
I again gave this position to Stockfish 7. At 35+ ply 1.Nxg3 has the edge over the pawn captures with a White advantage of about a third of a pawn (the advantage varied with each ply of depth). As expected, 1.hxg3 was better than the "ugly" capture 1.fxg3 but it was surprisingly close. Both still left White with about a 0.2 pawn advantage. So it turned out that in this case you could not go far wrong no matter which move you picked, but you don't know this ahead of time, so care is required.
Carlsen-Karjakin 8th WC Match Game 2016.
Which way would you recapture on c4? Check your local engine for the answer!
The bottom line is that one should NOT make any of these captures automatically for any one reason, but to take some time to weigh the pros and cons. Doing so will likely result in not only a better chance to find a superior move, but will gradually improve your evaluation abilities.
Remember, the goal each game is to use almost all your time without getting into unnecessary time pressure. If you finish a long time control game with substantial time on your clock, it's likely that taking more time on most of your moves would have resulted in superior play, no matter who you are or who you are playing!