Does anyone have any experience or opinions about the below variations? Are they playable for black, or only good as a surprise weapon, or not even that?

1. d4 g6 2. c4 Bg7 3. e4 d6 4. Nc3 Nc6 5. d5 Nd4
1. d4 g6 2. c4 Bg7 3. e4 d6 4. Nc3 e5
1. d4 g6 2. c4 Bg7 3. e4 d6 4. Nc3 c6

1. d4 d6 2. c4 e5
1. d4 d6 2. Nf3 Bg4

And which of these two systems would you rather recommend as a "repertoire" against 1. d4?

Thanks

Hey. I haven't used this in tournament practice, but I'm reading an explosive repetoire for Black which recommends these lines. One thing the authors warn early on though is that if you are put off by end games, DO NOT adopt these lines.

At C-class and below, you'll often get 3. dxe5 dxe5 4. Qxd8 Kxd8, because white players think that the exchange of queens and preventing black from castling is good for them. Practice shows that the game is actually better for black, black plans on locking down the center with moves like f6, and c6 and moves his king to the amazingly safe c7.

Some of those earlier lines you mention look like King's Indian variants. When I used to play tournaments, I was overly fond of the Benko gambit, something you might look into because its well playable for black and one need not memorize a gazillion lines to get through it. Black gives up a queenside pawn, but sets up rook and queen batteries on the a and b files, fianchettos his bishop on g7, gets a solid pawn formation, and.... has a wealth of tactical opportunities on White's b2 pawn. If white tries too arduously to hold onto his extra material, he could get into trouble.

It seems to me that in the first case White can aim to transpose into lines of the Saemisch where he gains a couple of tempi on the usual play, specifically the lines where white plays Ng8-e2-c1-e2 in response to a knight incursion on d4. White would play 6.Bc1-e3 and then 7.Ng1-e2. The original lines are quite playable for white and I imagine that they would be even better with two extra tempi.

The second line looks playable. I would probably play the third if I had to play one of these. It seems to be the most flexible.

Lines 4 and 5 look playable but would not be to my taste because in line 4 white can force an early queen trade and in line 5 consistency will probably require a trade of bishop for knight and this could lead to problems on the queenside.

Crash

I haven't made it through all the variations just yet, but I do know that the authors seem (uncomfortably) ambivalent about ... 1.d4 d6 2. c4 e5 3. Nf3 e4 4. Ng1....

For what it's worth ....


B.

The concensus, except the one I just cited is that black has the advantage or equalizes in almost all the lines featuring d4 ... d6.

I don't see how the game can possibly be better for black unless white plays it carelessly. I've played these positions quite a bit in speed (blitz) and have had no problem gaining at least a slight advantage as white. White often castles queenside but not always.

Typical development plans:
1.d4 d6 2.c4 e5 3.dxe5 dxe5 4.Qxd8+ Kxd8 5.Nf3
( 5.e4 c6 6.Nc3 Bb4 7.Ne2 Be6 8.b3 Nf6 9.f3 Nbd7 10.Bb2 Kc7 11.O-O-O )
5...f6 6.e4
( 6.Nc3 Bb4 7.Bd2 Be6 8.e4 Nh6 9.a3 Be7 10.Be2 c6 11.O-O-O Kc7 12.Ne1
Ng4 13.f3 Nh6 14.Nc2 Nf7 15.Ne3 )
6...c6 7.Be3 Nh6 8.h3 Nf7 9.Nfd2 Be6 10.Be2 Nd7 11.O-O Kc7 12.Rc1 *

1.d4 d6 2.c4 e5 3.dxe5 dxe5 4.Qxd8+ Kxd8 5.Nf3 f6 6.Nc3 Be6 7.e4 Nd7 8.Be2
c6 9.O-O Kc7 10.Be3 Bb4 11.Rac1 *

If you play the Benko you can expect to face many situations where players will decline the gambit or side-step by playing lines from the English (by transposition).

Crash

If that were so, it would be the main line. You have to be careful of analysis in monographs advocating a particular opening. It is not always objective.

Crash

but Bxf3 is only one option... I'm just getting through the material myself... so I can't help out much at this point. I'll get back to you on that!

Ok.. Crash... well, I'm not a high-level player so don't know about the exchange queens bit.. but I'll run it through my chess engine tonight and see what it has to say. On the monographs, quite right. That's one reason I like Richard Palliser, he pretty much admits when his advocated lines face difficulty.

Mednis calls 7... Qb6?! quite dubious citing 8.Qd2 Bg4 9.f3 Bxf3 10.Na4 Qa6 11.Nxd4 cxd4 12.Bxd4 Bxd4 13.Qxd4 Nf6 14.c5 Qa5+ 15.Nc3 dxc5 16.Qe5 Bg4 17.Bb5+ Kf8 18.d6 with a decisive attack (Schlehofer-Schultze, West Germany 1979). This analysis is old (1979) perhaps there are improvements for both sides.

(Keene gave it, 7... Qb6! in 1972)

7... Qb6 8. Na4 Qa5 9.Bd2 Qd8 10. Bc3 e5 11.dxe6 e.p. Nxe6 12.Bxg7 Nxg7 13.Qd2 Nf6

14.Nac3 OO 1-0(24) Soln 2280 - Marques, Brazil Wch U18 boys, 1995; 1-0(40) Soln 2380 - Armanda 2305, Ivan Cvitanovic Mem, Split Croatia 2000; 14...Qe7 1-0(22) Sarosy - Marcoux, corr CCCA 1976.

14.f3 Be6 1-0(58) Gelfand 2615 - Azmaiparashvili 2610, Dortmund 1990.

I have two books both titled "The Modern Defence" with the first by Keene and Botterill (1972) and the second by Hort with additional annotated games by Mednis (1979). I haven't bought any specific opening books yet since coming back. I did buy the general openings book Nunn's Chess Openings (1999) recently.
The player who played the line against me in blitz was an A player so maybe he wasn't finding the best lines. He told me about some analysis that said that it was better for black but I probably beat him ten out of ten so his argument about the analysis was not convincing to me.

Crash