Understanding Nimzo, Using His System
Temposchlucker has motivated me to pick again Nimzo's "My System" from my shelf. A second reason for doing this is that I have included Nimzoindian defense into my repertoire and I still have some deficits in understanding this concept. The concept of tempo and development is crucial in this opening, and after having read again the first chapters of “My System", I have come to important insights that I want to share with you.
My first, incomplete idea about this opening is Black giving up the bishop pair advantage which is compensated by a double pawn of White. But I did not like that White can “refute" this plan by playing 4.Qc2 (after 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4) in order to retake with the Queen, avoiding the double pawn. After 4.-c5, the best move in my opinion, we come to this position:
White to move. If he wants to win the bishop pair, he must invest a second tempo by 5.a3, Black takes Bxc3 and after 6.Qxc3 he is still two tempi ahead. And he gets even more after 6.-cxd4 7.Qxd4 Nc6 the Queen is forced to her fourth move and Black has a substantial lead in development. The ideas behind all these moves have been described in detail in the first chapters of “My System", using other openings, sometimes with unsound play of amateurs, but this is really great in this book: A GM who is ready to comment on patzer moves in order to make his ideas as clear as possible.
Aha, now I have got why theory does not recommend 5.a3 but 5.dxc5 Bxc5 and Black keeps his bishop pair. Thus, I think that 4.Qc2 is not the best idea of White.