Manual de Chess Position Trainer 4 2012 | Page 17

Chess Position Trainer – © Stefan Renzewitz 2012 - all rights reserved

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1.4.1 The concept of Position Database
In CPT not concrete games, but just positions and moves are saved – independent of any games. Of course, with
this information it’s possible to re-calculate a move order to reach a certain position, but in general the approach
is very different to typical chess databases, because the goal of CPT is quite different too. So, please unlearn to
think in terms of games for the opening repertoire module.
One major difference of a position database is that the program covers transpositions within the same opening
or across openings (even repertoires). Especially with openings which transpose quite often you will soon appreciate this feature. Every position and move is unique in the database. The same position or move (for a certain position) is never saved twice. If you add a comment to a position or move and it is part of two openings it
will be shown for both openings the same. If you edit the comment for one opening the updated comment is
shown for the other opening. The same is true for position or move evaluation or training result. However, you
can decide to exclude a move for a given position for an opening. For example you might play the Closed Sicilian for both sides. Then you are not forced to maintain all moves for both sides. Instead you will most likely
have for the opposite color all possible replies and for your side just one. Also you can have different rankings
of your candidate moves per opening.

1.4.2 The concept of Candidate Moves
In general you study some chess material and make decisions about which variations lead to middle game positions you want to reach no matter what your opponent plays. This requests some effort on your side as you have
to make sure that on the way to those positions your opponent can’t play let’s say a drawish variation.
Now, to achieve your goal you have to decide for each position (beginning with the start position) what you
want to play keeping in mind that it is supposed to be guaranteed to lead to one of your favourite variations and
finally positions. Thus you have usually just one move for your side, but you have to consider several moves for
your opposite side, because you can’t legally force your opponent to play your preferred variation. However, by
your choice you restrict the reasonable options for your opponent and this is exactly the effort you have to
make: whatever he plays you have to ensure you still have one move which leads to a variation / position which
you prefer to play. Wait a moment and let this sink into your brain. Re-read this paragraph as it is key to the
whole opening module and CPT in general. If you have never heard about the concept of candidate moves it can
be confusing at first.