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Grivas Chess Lab - The Principle of the Two Weaknesses 

GM Efstratios Grivas September 24, 2025

Sequence:  Advanced Strategy  »

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3h and 20 min PGN Download Video Content


Content  (120 Articles)

Introduction and Free Preview  Free
GM Efstratios Grivas - Video CV  Closed
Video Chapters Break  Closed
Video Introduction  Closed
Introduction  Closed
Fighting on All Sides - The Boxer Effect  Closed
Chapter A - Middlegame Principles  Closed
Chapter A1 - Open File  Closed
Karpov, Anatoly - Unzicker, Wolfgang - Video Lecture  Closed
Karpov, Anatoly - Unzicker, Wolfgang  Closed
Grivas, Efstratios - Genov, Petar - Video Lecture  Closed
Grivas, Efstratios - Genov, Petar  Closed
Rivas Pastor, Manuel - Rodriguez Guerrero, Enrique  Closed
Sargissian, Gabriel - Yu, Yangyi  Closed
Chapter A2 - Semi-Open File  Closed
Chekhover, Vitaly - Rudakovsky, Iosif - Video Lecture  Closed
Chekhover, Vitaly - Rudakovsky, Iosif  Closed
Grivas, Efstratios - Velikov, Petar  Closed
Grivas, Efstratios - Skalkotas, Nikolaos - Video Lecture  Closed
Grivas, Efstratios - Skalkotas, Nikolaos  Closed
Grivas, Efstratios - Ilandzis, Spyridon  Closed
Grivas, Efstratios - Klimis, Laertis  Closed
Grivas, Efstratios - Blatny, Pavel  Closed
Chapter A3 - Weaknesses All Around  Closed
Vogt, Lothar - Andersson, Ulf  Closed
Rosen, Eric - Li, Marissa  Closed
Grivas, Efstratios - Kokkinos, Leonidas  Closed
Grivas, Efstratios - Kanakaris, Georgios - Video Lecture  Closed
Grivas, Efstratios - Kanakaris, Georgios  Closed
Grivas, Efstratios - Priyanka, Nutakki - Video Lecture  Closed
Grivas, Efstratios - Priyanka, Nutakki  Closed
Grivas, Efstratios - Pandavos, Panayiotis  Closed
Grivas, Efstratios - Karagiannis, Athanasios  Closed
Grivas, Efstratios - Papas, Konstantinos - Video Lecture  Closed
Grivas, Efstratios - Papas, Konstantinos  Closed
Chapter A4 - Pawn Islands  Closed
Lasker, Emanuel - Capablanca, Jose Raul - Video Lecture  Closed
Lasker, Emanuel - Capablanca, Jose Raul  Closed
Grivas, Efstratios - Haritakis, Theodoros - Video Lecture  Closed
Grivas, Efstratios - Haritakis, Theodoros  Closed
Grivas, Efstratios - Vihaan, Dumir  Closed
Chapter B - Endgame Principles  Closed
Chapter B1 - Alekhine's Contribution  Closed
Thomas, George Alan - Alekhine, Alexander - Video Lecture  Closed
Thomas, George Alan - Alekhine, Alexander  Closed
Alekhine, Alexander - Euwe, Max - Video Lecture  Closed
Alekhine, Alexander - Euwe, Max  Closed
Alekhine, Alexander - Vidmar, Milan Sr  Closed
Alekhine, Alexander - Saemisch, Friedrich  Closed
Chapter B2 - Rook Endings  Closed
Flohr, Salo - Vidmar, Milan Sr - Video Lecture  Closed
Flohr, Salo - Vidmar, Milan Sr  Closed
Lein, Anatoly - Littlewood, Paul - Video Lecture  Closed
Lein, Anatoly - Littlewood, Paul  Closed
Chapter B3 - Evaluation  Closed
Example 1 - The Principle of the Two Weak  Closed
Example 2 - The Principle of the Two Weak  Closed
Szabo, Laszlo - Penrose, Jonathan - Video Lecture  Closed
Szabo, Laszlo - Penrose, Jonathan  Closed
Grivas, Efstratios - Renet, Olivier  Closed
Grivas, Efstratios - Karagiannis, Athanasios  Closed
Shavtvaladze, Nikoloz - Grivas, Efstratios - Video Lecture  Closed
Shavtvaladze, Nikoloz - Grivas, Efstratios  Closed
Makridis, Efstathios - Grivas, Efstratios - Video Lecture  Closed
Makridis, Efstathios - Grivas, Efstratios  Closed
Chapter B4 - Theoretical Weaknesses  Closed
Example 3 - The Principle of the Two Weaknesses  Closed
Example 4 - The Principle of the Two Weaknesses  Closed
Kotov, Alexander - Pachman, Ludek - Video Lecture  Closed
Kotov, Alexander - Pachman, Ludek  Closed
Byrne, Robert Eugene - Eliskases, Erich Gottlieb - Video Lecture  Closed
Byrne, Robert Eugene - Eliskases, Erich Gottlieb  Closed
Megaranto, Susanto - So, Wesley  Closed
Smyslov, Vassily - Keres, Paul  Closed
Chapter B5 - Rocket Transfer  Closed
Kotov, Alexander - Pachman, Ludek  Closed
Byrne, Robert Eugene - Eliskases, Erich Gottlieb  Closed
Megaranto, Susanto - So, Wesley  Closed
Smyslov, Vassily - Keres, Paul  Closed
Example 4 - The Principle of the Two Weaknesses  Closed
Jachym, Marc - Grivas, Efstratios - Video Lecture  Closed
Jachym, Marc - Grivas, Efstratios  Closed
Hutchings, Stuart James - Keene, Raymond  Closed
Hug, Werner - Barle, Janez  Closed
Janowski, Dawid Markelowicz - Capablanca, Jose Raul - Video Lecture  Closed
Janowski, Dawid Markelowicz - Capablanca, Jose Raul  Closed
Rubinstein, Akiba - Takacs, Sandor  Closed
Chapter B6 - Defense  Closed
Karpov, Anatoly - Parma, Bruno - Video Lecture  Closed
Karpov, Anatoly - Parma, Bruno  Closed
Faibisovich, Vadim - Westerinen, Heikki MJ  Closed
Chapter B7 - Long Battles  Closed
Grivas, Efstratios - Avrukh, Boris - Video Lecture  Closed
Grivas, Efstratios - Avrukh, Boris  Closed
Grivas, Efstratios - Bach, Matthias  Closed
Alekhine, Alexander - Chajes, Oscar  Closed
Grivas, Efstratios - Bricard, Emmanuel  Closed
Kramnik, Vladimir - Illescas Cordoba, Miguel  Closed
Ilandzis, Spyridon - Grivas, Efstratios  Closed
Capablanca, Jose Raul - Tartakower, Saviely  Closed
Chapter B8 - Domination  Closed
Smyslov, Vassily - Ernst, Thomas  Closed
Dreev, Alexey - Hansen, Curt  Closed
Shereshevski, Mikhail - Beliavsky, Alexander  Closed
Benko, Pal - Parma, Bruno  Closed
Grivas, Efstratios - Khetsuriani, Besarion - Video Lecture  Closed
Grivas, Efstratios - Khetsuriani, Besarion  Closed
Orfanos, Lefteris - Grivas, Efstratios - Video Lecture  Closed
Orfanos, Lefteris - Grivas, Efstratios  Closed
Chapter B9 - Extra Material  Closed
Tartakower, Saviely - Boleslavsky, Isaak  Closed
Von Holzhausen, Walther - Nimzowitsch, Aron - Video Lecture  Closed
Von Holzhausen, Walther - Nimzowitsch, Aron  Closed
Exercises - Solutions  Closed
Grivas, Efstratios - Adamidis, Ilias  Closed
Grivas, Efstratios - Burgess, Mark  Closed
Grivas, Efstratios - Sarwat, Walaa  Closed
Grivas, Efstratios - Kanavarakis, Dimitrios  Closed
Alekhine, Alexander - Bogoljubow, Efim  Closed
Carlsen, Magnus - Eljanov, Pavel  Closed

79.00 EUR

The Principle of the Two Weaknesses: GM Efstratios Grivas Continues the Chess Lab Series Comprehensive Analysis Through 68 Annotated Games Across All Phases of Play

Modern Chess presents the second installment in the Grivas Chess Lab series: The Principle of the Two Weaknesses. Following his definitive work on Endgames with Opposite-Colored Bishops, GM Efstratios Grivas provides a systematic examination of chess's most reliable winning principle through 68 carefully selected and extensively annotated games.

The Strategic Framework for Converting Advantages

"One sick pawn can lose you the game, but you need two points of attack to win," explains GM Grivas, highlighting the fundamental paradox in positional chess. The Principle of the Two Weaknesses, formulated by Aron Nimzowitsch in "My System," provides the systematic approach for converting positional advantages into decisive results.

This course addresses the gap between recognizing weaknesses and systematically exploiting them, featuring games by Alekhine, Capablanca, Karpov, Smyslov, Kramnik, and extensive analysis of GM Grivas's own instructive victories.

The Boxer Effect: Coordinated Pressure Application

The course introduces GM Grivas's "Boxer Effect" concept—the systematic application of alternating pressure on multiple fronts. This framework demonstrates how attacking one weakness then switching to another gradually overwhelms defensive resources.

Part A: Middlegame Applications Through Four Strategic Contexts

Chapter A1: Open File Control (4 games) Analysis begins with Karpov-Unzicker and includes Grivas-Genov, Rivas-Rodriguez Guerrero, and Sargissian-Yu, demonstrating the coordination between file pressure and distant structural weaknesses.

Chapter A2: Semi-Open File Exploitation (6 games) Six detailed studies including Chekhover-Rudakovsky and multiple Grivas games (Velikov, Skalkotas, Ilandzis, Klimis, Blatny) show practical conversion techniques when controlling semi-open files.

Chapter A3: Complex Middlegame Weaknesses (8 games) From Vogt-Andersson to various Grivas encounters (Kokkinos, Kanakaris, Priyanka, Pandavos, Karagiannis, Papas), these examples demonstrate the principle in positions with multiple structural defects.

Chapter A4: Pawn Island Theory (3 games) The theoretical foundation through Lasker-Capablanca, supplemented by Grivas-Haritakis and Grivas-Vihaan, exploring how pawn structure determines strategic plans.

Part B: Endgame Applications Through Nine Technical Areas

Chapter B1: Alekhine's Contribution (4 games) Analysis of four games by the 4th World Champion, including encounters with Thomas, two games with Euwe, and the instructive win against Saemisch.

Chapter B2: Rook Ending Technique (2 games) Flohr-Vidmar and Lein-Littlewood demonstrate the principle's application in rook endings, where precise technique determines outcomes.

Chapter B3: Position Evaluation (7 games) Seven examples including theoretical positions and practical games like Szabo-Penrose and multiple Grivas encounters, teaching accurate assessment of two-weakness scenarios.

Chapter B4: Theoretical Applications (6 games) Essential theoretical knowledge through Kotov-Pachman, Byrne-Eliskases, Megaranto-So, and Smyslov-Keres, providing the foundation for practical understanding.

Chapter B5: Piece Transfer Technique (5 games) The coordination of forces through Jachym-Grivas, Hutchings-Keene, Hug-Barle, Janowski-Capablanca, and Rubinstein-Takacs.

Chapter B6: Defensive Resources (2 games) Karpov-Parma and Faibisovich-Westerinen demonstrate proper defensive technique and the limits of resistance against two-weakness attacks.

Chapter B7: Extended Struggles (7 games) Seven lengthy encounters including Grivas-Avrukh, Grivas-Bach, Alekhine-Chajes, Capablanca-Tartakower, and others showing patience and technique in complex positions.

Chapter B8: Positional Domination (6 games) Complete strategic control through Smyslov-Ernst, Dreev-Hansen, Shereshevski-Beliavsky, and three additional examples of systematic exploitation.

Chapter B9: Material Advantage Applications (2 games) Tartakower-Boleslavsky and Von Holzhausen-Nimzowitsch demonstrate why the principle applies even with material superiority.

Practical Training Six exercises with detailed solutions through additional games: Grivas-Adamidis, Grivas-Burgess, Grivas-Sarwat, Grivas-Kanavarakis, Alekhine-Bogoljubow, and Carlsen-Eljanov.

Author Credentials GM Efstratios Grivas brings established expertise:

Course Structure and Formats

PGN Database: 68 annotated games with detailed commentary suitable for database study Video Analysis: 3 hours 20 minutes of visual instruction covering key concepts and critical positions
PDF Reference: Downloadable comprehensive guide for offline study and reference

Technical Focus The course emphasizes practical application over theoretical memorization. Each game selection serves specific instructional purposes, with annotations that reveal both strategic planning and tactical execution. The analysis maintains competitive playing standards while providing clear explanations for systematic improvement.

Series Continuation This course builds on the analytical foundation established in GM Grivas's opposite-colored bishop course, continuing the Grivas Chess Lab series commitment to comprehensive theoretical treatment combined with practical applicability.

For players seeking systematic understanding of advantage conversion through documented analysis and proven technique, The Principle of the Two Weaknesses provides the complete theoretical and practical framework.

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