nestor - Thanks for the information. For some reason, I was suspecting that Krishnater's suggestion would be something other than 6...Ne7. Perhaps because the list of chapters referred to the "Winawer main line" rather than the "Main Line Winawer". At any rate, 6...Nc6 was initially a surprise to me. On further reflection, it's understandable since the move has become popular in the last couple years.

Getting back to The French Defense Revisited and Reply #37 specifically, I was hoping that additional information on the relative merits of 7...Qc7 and 7...Qa5 vs 7.h4 might eventually be obtained from Beat the French Winawer Variation by Kotronias and Ivanov. This book supposedly recommends meeting the Winawer with 7.h4 and has been displayed on the "Expected" page of the Thinkers Publishing website for quite some time.  However, I recently saw that this page was undated in February, and the Winawer book is no longer shown.  An email inquiry to the publisher has gone unanswered, so it's looking like the book has been cancelled. On a more positive note, Modern Chess has just released Modern French Defense: Complete Repertoire for Black by IM Kushager Krishnater. It appears to be a video course that was originally released by thechessworld, but the Modern Chess version has the advantage of having the variations available in PGN form as well.  Krishnater recommends the Winawer, but it's not clear to me from the chapter list for the course if he's covering 7.h4 or avoiding it with something like the Portisch-Hook variation (6...Qa5).

I came across IM Andras Toth praising the Sokolov book and talking about some of the Winawer content.
https://www.youtube.com/watch?v=2Gs-zWMr-kg

Regarding the positional Winawer stuff, I wonder if Ivan Sokolov has anything to say about it in his new book. (It's "not a theory book"; it's about some 1. e4 structures, and has a Winawer chapter.)

I see that the position before 18. Nf6 in Golyak-Gaiduk appeared in Pachman's Modern Chess Tactics (1973), and was used (giving Pachman as the source) in the Bratko-Kopec Test (1982).

Alexey Suetin in his 1965 book Modern Chess Opening Theory thought that 8...c4 "leads to a complicated game with approximately equal chances for both sides."

kylemeister - Thanks for pointing out the So-Abdusattorov game in Reply #27. I was curious about the position after 9...c4 and found that its first occurrence in the Mega Database was in the famous Smyslov-Botvinnik game from the 1944 Soviet Championship. The Chessbase version of the game was annotated by Rainer Knaak, who marked 9...c4 with a ?. He noted that Black usually waits for White to commit to Bf1-e2 before advancing the c-pawn. He felt that closing the position with 9...c4? was weak since White can develop the bishop to g2 or h3 (obviously after g2-g3). This is similar to the Nunn/NCO line that you mentioned.

It turns out that Smyslov-Botvinnik is the first game in Giddins' The French Winawer Move by Move. Giddins is more charitable, marking 9...c4 with !?. He says that it's more common to retain the central tension with 9...Bd7 and adds that 9...c4 would allow 10.g3 with the idea of Bh3, O-O,  Nh4, and f4-f5, which is also the same general idea of the flank development of the bishop given by Knaak and Nunn.

Another old book bit is Moles' analysis in his The French Defence - Main Line Winawer. He follows Boleslavsky-Barcza for several moves: 10.g3 Bd7 11.Bg2 0-0-0 12.0-0 f5 13.exf6 gxf6 14.Re1 Ng6 15.Bh6 Rhg8 16.Qd2 Rde8. Now Moles quotes an even older book, Schwarz, which has an evaluation of =/+. In contrast, Stockfish gives White a slight edge. Moles called 10.Bg2 "illogical" and preferred 10.Bh3. He quotes the game Raetsch-Liebert, Lasker Memorial Berlin 1962, where White achieved a winning edge but then "went off the rails" and lost. In introducing his section on 9...c4, Moles says the move "is considered inaccurate since Black has nothing to fear from 9...Bd7 10.c4 and theoretically should wait for White to commit his king bishop to e2 or d3 before closing the queenside." He concludes the section with  "White seems to have chances for the initiative with 10.g3; hence Black should avoid 9...c4, which has no special counter-virtues to justify the inconvenience of having to meet 10.g3".

In line with his comment of waiting for White to play Bf1 e2 or Bf1-d3, Moles considers 9...Bd7 10.Be2 c4 to be fine. It's his main line, as I noted back in Reply #16.

So the consensus from 1975 (Moles) to 2013 (Giddins) seems to be that 9...c4 is premature, and it's better to wait for White to develop his king bishop. More recently, however, 9...c4 has been played with some regularity.  ChessBase marks 9...c4 as a "hot" move.  Thus, it could be part of the apparent trend of Black closing the position by advancing his c-pawn and thereby aiming to play more strategically. It's interesting that Abdusattorov played the move. He's the strongest player to adopt it in recent years, although it was "just" in a blitz game.

Dink Heckler wrote on 10/06/23 at 11:14:59:

I agree.  It was rather unsettling to open that new edition of ECO and find that switch.

Orthogonal to the main discussion, but I never realised that ECO codes changed - seems disconcerting.

Reminds me of the Simpson's quote:
"I used to be with 'it', but then they changed what 'it' was!"