While checking on Prusikin's analysis of the KIA in his book Countering the Queen's Gambit, I noticed he uses the move order 1.Nf3 d5 2.g3 Nf6 3.Bg2 e6 4.0-0 Be7 5.d3 c5 6.Nbd2 b5 7.e4 Bb7 8.Re1 Nc6. IM Schuh, in his book review, has Black playing 6...Nc6 and then 7...b5 and 8...Bb7.

With respect to keeping options open, after 5...c5, Prusikin comments, "...Black would like to defer castling for a long time or even not play it altogether. As a result, the assault on the kingside planned by White comes to nothing." The review by Schuh mentions delayed castling, but Prusikin's actual words go further by indicating that Black might not play the move at all.

After 9.e5 (which is marked ?!), Prusikin continues 9...Nd7 10.Nf1 a5 11.h4 h6! 12.N1h2 a4 13.a3 Qb6, which he evaluates as ⩱. (Stockfish also gives ⩱). He says at this point, "Black leaves the king in the middle or even castles queenside. He has a simple plan on the queenside, while White has a hard time generating counterplay on the other side of the board." 

I haven't previously seen this plan of keeping the Black king in the center in the KIA, but it seems to work here. It should be noted that omission of castling isn't a feature in all of Prusikin's lines. For example, after 9.exd5 Nxd5 10.Ne4, he gives 10...0-0!, saying "...now that the center is open, Black can castle safely." His comment seems to imply that White can't generate his usual formulaic attack with an open center, but I also wonder if it's now prudent to castle given that opening.

After 1. Nf3 d5 2. g3 Nf6 3. Bg2 e6 4. O-O Be7 5. d3 c5 6. Nbd2 Nc6 7. e4, most games and theory continues with 7...O-O. I think of this as the pinata variation. Many games have proceeded 8. Re1 b5 9. e5 Nd7 10. Nf1 a5 11. h4 with double-edged play.



7...b6 8. Re1 Bb7 is less explored. Black keeps his options open regarding his king.



It has been examined by theory and games and continues to be played. It's a bit murky as both sides may keep their options open for a while. While the path forward may be narrower for Black than for White, it's still an interesting option. 9. Qe2 Qc7 10. c3 h6 11. h4 a5 12. a4 Ba6 13. e5 Nd7 14. h5, and now instead of 14...0-0-0?!, the move one would want to play, 14...Bg5 may keep the balance.



Thanks Tony for fixing this up. Somehow, I ended up with multiple posts.

Kylemeister, I'll look at ...b5 when I get the chance.

FreeRepublic wrote on 06/27/24 at 13:08:55:

"Our general idea is to play Bc5 and Qe7 with a comfortable position due to the passive bishop g2."

So Black is basically playing an old book line (from 1. e4 e6 2. d3) but "sacrificing" a tempo with his KB. (An example of the old version is Vasiukov-Tal, USSR ch 1961. As I recall, Tal annotated part of that game in his "Life and Games" book.)

Another sideline commences with 6...Nc6. 

(1. Nf3 d5 2. g3 Nf6 3. Bg2 e6 4. O-O Be7 5. d3 O-O 6. Nbd2 Nc6)

ChessPub: "was another Aronian favourite analyzed in Rapport-Aronian in the Archives. Black  to occupy the centre with 7...e5."

It is also recommended by GM Lysy at Modern-Chess.
https://www.modern-chess.com/setups-with-g2-g3-universal-solution-for-black-part...

He says:

"Over the years, I have responded with 5...0-0, 6...c5, and 7...Nc6, achieving excellent positions but poor results. Two years ago, I took note of Nakamura's games after 6...Nc6, with the idea of placing the black pawn on e5."

There is a sample chapter that covers this, at least in part.

I've looked at that in the related French positions.

Also unsurprisingly it's something the Neural Net engines like But it does make sense - you want to see how white is going to react on the queenside, then you can arrange your Q-side play in response.

I have no idea how it goes if white goes for c4 rather than e4. I suppose then you're mostly discouraging b3 ideas and asking what else white is going to do to develop!

Here's another variation in this complex:

1. Nf3 d5 2. g3 Nf6 3. Bg2 e6 4. O-O c5 5. d4!? cd4 6. Nd4 e5



It's been played by strong players from Polugaevsky-Korchnoi 1977 to Gelfand-Keymer 2023. Yet as far as I know it does not have a name, and games can be found under various ECO codes.

Nernstian59 wrote on 06/09/24 at 22:41:25:

I too thought of that book, which is 50 years old this year. I don't know if the comment on overprotection appeared in the two editions of Flank Openings which preceded it (1967 and 1970).

In Becoming a Grandmaster (1977), Keene wrote that "I had turned the literary skills acquired at Cambridge towards a 'Reappraisal' of my chess hero, 'Aron Nimzowitsch' and the end of 1972 and much of 1973 was spent in contemplation of his games in preparation for the relevant volume. Several masters have observed a marked upswing in their own play after a deep study of a great predecessor. Kotov was another example. He made great strides after his book on Alekhine, and this kind of creative examination is certainly a course I can recommend to any aspiring GM."