## Saturday, August 11, 2012

### Between positional and tactical

The past week I analyzed the tactical elements of about 150 problems at CT with a rating of 2000+.
I found the following tactical elements:
• Double attack
• Discovered attack
• Pin
• Skewer
• Invasion
• Hanging piece
• Promotion
At average a problem contained 6-10 tactical  elements for the attacking side and 1-3 elements for the defending side.

This opens up a whole area of preliminary moves between positional moves and the actual execution of a tactical element.

The goal of a positional move is to diminish the posibilities of the opponent relatively to your own possibilities. The goal is to limit the possibilities of your opponent to such extend that he can no longer meet your threats. When that moment arises, you can execute a tactical element.

There are the typical positional moves like gaining space, get an outpost, occupy an open line etc. to work on the relative possibilities of the two sides. But between a positional move and the final execution of a tactical element, a whole area of prelimanary tactical moves submerges.

The problems of CT are derived from real games. If a problem contains 6-10 tactical elements what does that mean? It means that the player during the game has put 6-10 tactical elements into place. That doesn't happen overnight. There are at least 6-10 moves necessary to install these tactical elements. Probably more.

Every tactical element does need one or more defenders to prevent it from execution. This means that the possibilities of the opponent are greatly diminished by binding defenders to tactical elements. When there are 6-10 tactical elements, there are at least 6-10 defenders needed to prevent them from execution. A winning combination prevails once all important defenders are bound and you can pose a threat that cannot be met. That are the kind of problems CT is presenting us.

In practical play, the amount of tactical elements that is needed may vary greatly. One defender can defend against one or more threats. When a defender defends against more than one threat, that might mean that the defender is overworked. The execution of a tactical element starts when the opponent has run out of defenders. A cramped position on the board (or a blunder) might cause that on a certain part of the board your opponent runs out of defenders rather soon. In case of an overworked piece, you execute one of the threats, thus decoying the defender from the other threat(s) he was defending. Bottomline is that the execution of a combination starts when there is at least one tactical element without defender.

1. I added a paragraph at the end for clarification.

2. I hardly get puzzles over 2000. But I have considerable experience of one class below: the 1800-2000 range.
And I can compare them with puzzles below that range. In the following I will call the 1800-2000 "hard" and the puzzles below 1600 "easy":

if the hard ones are a fork, then they have typically forks of equal
pieces:
knights forking knights, queen forking queens, rook forking rooks, bishop forking bishops.

If they are a distraction/attraction, then often a queen distracts a queen.
Again, equal tags with equal pieces are usually higher rated.

Then there is the element of repetition: you give a check while at the same time take a pawn. The opponent king moves, and you give another check. The king moves back to its origin. Then you go back with the check giving piece to its origin. We have almost the same position on the board, but the difference is the missing pawn which you took with a check.

People seem to discard options if they have the feeling that they are just a repetition back to the origin (seemingly making no "progress"). It does not matter that it is obvious. If the puzzle had started without the pawn, it could have been a 1100 rated puzzle.
We seem to be blind for going back to squares we came from.
The nature of tactics are, that they are often forward executed. Forwards against opponents pieces.
That is why most hard puzzles whose solution is a "going back to the original position" show a "backward" move, or at least a "sidemove".

After doing some hundreds of hard puzzles, I developed a sense for "going back to the original position". I do consider going back to where I just came from. Well, at least more often than before...
(nobody is perfect).

What has all this to do with your post here? Well, you discussed the nature of a tactic, with defenders who are overworked. I just felt like adding a bit more detail about what kind of pieces are overworked (hard puzzles overwork often equal pieces). And the "backward" move nature of hard puzzle has indeed not much to do with your post, but well, I have written it, I dont delete it.

3. I wonder what invasion is?

As always I find that you write as an essayist. So hard to completely grasp your meaning, nevertheless always intreresting points you bring up.

I wonder if have a tactical list in your mind during play which you check from 1 to ... each time its your move in a game?

4. @CT,
a possible invasion square (or file or row or diagonal) is a square inside enemy territory at which your pieces converge. If there are insufficient defenders, you can invade there. Often this leads to new threads.

During a game there is no time to fiddle around with checklists. The method I propose is meant for the study room and is designed to educate the chess module in your brain that cranks out moves during a game.