Monday, June 25, 2012

Gambit Hubsch - Antidote ou Leurre ?

This week, I received Eric Jego's book "Gambit Hubsch - Antidote ou Leurre ?".

Eric's book is in French - "leurre" can be translate in English as "bait", or "decoy". And that word illustrates the concept of the book very well. Eric tries to explain the applicable ideas in the various Hubsch lines. I like his work, especially for following reasons :

1. As always with Eric's books, the layout is great and facilitates the reading. It is obvious Eric has spent lots of time on it. Just look at the art work on the front page and you will know what I talking about !

2. Eric focuses on games between titled players. I focus more on (computer) opening analysis, but it is great to see how strong players react on white's enterprising play. Guess this gives confidence to the reader that strong player make errors too. In my books and blog, I am looking into it differently, but Eric's work is equally valuable.

3. I like the comments section at the end of each variation. It summarises the ideas quite well ( an area I have not focused on in my book on the Blackmar Diemer ).

4. In comparison with his previous book, Eric has focused less on the application of the "elementary principles". Eric does a remarkable job of applying them in the right dosing throughout the text.

5. "Gambit Hubsch - Antidote ou Leurre ?" does not focus on single variations but provides a wide look into all variations. This broadens the scope of the book, and reader.

Some (minor) concerns I have :

1. The physical size and used font seem to small as I had problems reading it in bed. Now reading chess books in bed might not be recommended, but it happens. So I would recommend increasing the book and associated font size a bit - which will make life easier.

2. Whilst Eric does a remarkable job in describing possible variations, the lines he analyses are not analysed very deeply. As an example, I have played the Hubsch twice against IM masters, both played exactly the same line 1.d4 Nf6 2.Nc3 d5 3.e4 Nxe4 4.Nxe4 dxe4 5.Bc4 Nc6 6.c3 e5 7.d5 (diagram). Now one IM played 7...Ne7, the second played 7...Nb8. I never saw the pawn back and was simply crushed. It can be coincidence that they played the same line, but from the smalltalk after the game, it seems they both knew about the Hubsch and this was their prepared reply. So thorough analysis and opening analysis seems necessary  when playing sharp lines. Eric's book seems not targeted towards this deep analysis.

So I really recommend this book to anyone studying the Blackmar Diemer - reading this book will keep you posted on that annoying Hubsch gambit. But is it now a refutation, or is it a trap ? It's up to you to find out !

Monday, June 18, 2012

Houdini versus Stockfish

I downloaded Stockfish today and tried to compare it to Houdini. I started the analysis on 5...g6, the starting point of the Bogoljubow defense (diagram).

First I tried Houdini 1.5a 64 bit, with 4096 MB memory. Houdini suggests 6.Bc4 untill a depth of 20 (49" thinking time ), then switches to 6.Bf4. After 5' thinking, it gives black an advantage of 0,17.

Stockfish 222 64 bit with 4096 MB memory suggests 6.Bb5+ c6 7.Bd3 untill 3', then switches to 6.Bc4. Only after 5' 31", Stockfish considers 6.Bf4 to be best, with a rating of 0,32 in blacks advantage.

So it seems both engines arrive at the same conclusion, but Houdini does it considerably faster ( at least in this position ). Also, Houdini seems to be more optimistic for the attacker.

After 6.Bf4 Bg7 7.Qd2 00 8.000 (diagram), Stockfish recommends 8...Nbd7 with an advantage of 0,40, whilst Houdini first suggests 8...Bf5, then 8...Bg4 with a black advantage of 0,20.
Delving a bit deeper in Stockfish's suggestion of 8...Nbd7, Houdini suggests 9.Kb1, whilst Stockfish believes 9.h3 is best.

The last position that I investigated is after 5...g6 6.Bc4 Bg7 7.00 00 8.Qe1 Nc6 9.Qh4 Bf5 (diagram). Stockfish suggests 10.h3 Na5, whilst Houdini plays it differently with 10.Bg5.

So it seems that the Blackmar Diemer gambit brings disagreement even under the strongest chess engines ! And you would expect that humans can form an objective assessment of the unbalanced positions that result after white's enterprising play, such as the Studier line in the Bogoljubow.

Wednesday, June 13, 2012

Why waiting moves are ( sometimes ) great

I was wondering why my computer sometimes suggests waiting moves. As an example, in the position occurring after 1.d4 Nf6 2.f3 d5 3.e4 dxe4 4.Nc3 exf3 5.Nxf3 g6 6.Bf4 Bg7 7.Qd2 00 8.000 Nc6 9.d5 ( gaining space )  Nb8 ( only option as 9...Nb4 10.a3 and 9...Na5 10.Nb5 with slight white advantage ), my computer now suggests 10.Kb1 (diagram).

Why is this waiting move better than the natural development move 10.Bc4 ?

Let's look first at 10.Bc4. Obviously, black wants to generate counterplay on the queenside, so 10...a6 is the obvious choice. White can not block this by 11.a4, since 11...b5 would open up the file for the rook. The alternative 11.a3 is surely better, but again allows black gaining space with 11...b5. So playing 10.Bc4 allows black to counterattack on the queenside.

Is this counterattack possible after the waiting 10.Kb1 ? The immediate 10...b5 11.Bxb5 is certainly not possible, so black needs to prepare this advance first. He can do so in two ways : a6 and c6.

The first option 10...a6 is countered by 11.Be2 (diagram)

The thematic 11...b5 is now answered by 12.Ne5. If black continues attacking like a madman with 12...b4, then white finds a great spot on the rim after 13.Na4. A knight on the rim is often dim - as the saying goes. But this is not the case here, as the white horseman can lateron move to the outpost c5, which is not guarded anymore by a pawn. Charging away the knight from his outpost with 12...Nbd7 is deadly, as c6 is not guarded anymore by a pawn.

The other way of preparing b5 is 10...c6, but now white delves deeper in enemy territory with 11.d6, followed by 11...exd6 12.Bxd6 Re8 and only now 13.Bc4 (diagram).
Black's counterattack 13...b5 is not to be feared after 14.Bb3 as 14...a5 is countered by 15.Qf4 and white's pieces are everywhere. The option of 14...b4, chasing away the knight, is not available in this position with the bishop on d6. So black has only 14...Be6 15.Bxe6 Rxe6 16.Qf4 with an equal game.

Lessons learned ? As an attacker, don't allow the defender a counterattack by exposing your pieces to rapidly, without them having an immediate threat. Consider a waiting move instead, urging the defneder to choose a defnese first - then attack. However, guess this approach is not the preferred choice for Blackmar Diemer gambiteers...

Wednesday, June 6, 2012

Refuted for the wrong reason

Several “experts” have refuted the Blackmar Diemer gambit based on the Ziegler position. Traditionally, white attacked like a berserker in the line 1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 c6 5.Bc4 exf3 6.Nxf3 Bf5 7.Ne5 ( better is 7.Bg5 ) e6 8.00 Bg6 and now the berserk move 9.g4 (?!).

Unfortunately, white’s last move does not attack anything and black has time to challenge the white knight. This can be done in two ways : 9…Nbd7 and 9…Bd6. The critics have suggested 9…Nbd7 to prove that the Blackmar Diemer gambit is refuted. But is this line really that bad ? White certainly has nothing else but 10.Nxg6 hxg6 11.g5 (diagram)

Let's look at this position now :

a/ 11…Qc7 (the “refutation” appears) 12.Qe2 (diagram)
…a1/ 12…Bd6 13.Rf2
……a1a/ 13…Nd5 14.Bxd5 cxd5 15.Nxd5 (=)
……a1b/ 13…Nh5 14.Ne4 (=)
……a1c/ 13…Nh7 14.Ne4 (=)
……a1d/ 13…Ng8 14.Rxf7 (=)
……a1e/ 13…Rh4 14.gxf6 Nxf6 15.Bg5 (=)
…a2/ 12…Nd5 13.Bxd5 cxd5 14.Nxd5 (=)
…a3/ 12…Nh5 13.Rxf7 (+=)
…a4/ 12…Ng8 13.Rxf7 (+)
…a5/ 12…Nb6 13.Bxe6 fxe6 14.gxf6 (+=)
…a6/ 12…000 13.gxf6 Nxf6 14.Bf4 Bd6 15.Bxd6 Qxd6 16.Rad1 (=)

b/ 11…Nd5 12.Qf3
…b1/ 12…f5 13.gxf6 (=)
…b2/ 12…f6 13.Re1 (=)
…b3/ 12…Qe7 13.Nxd5 (=)

c/ 11…Nh5 12.Qf3 (+=)

d/ 11…Nh7 12.Qg4 (=)

e/ 11…Nb6 12.Bxe6 fxe6 13.gxf6 gxf6 14.Qg4 (diagram)

…e1/ 14…Kd7 15.Qxg6 (=+)
…e2/ 14…Kf7 15.Bg5 (=)
…e3/ 14…f5 15.Qxg6+ Kd7 16.Rf3 (=+)
…e4/ 14…Bg7 15.Qxg6+ Kf8 16.Ne4 (+=)
…e5/ 14…Be7 15.Qxe6 (=+)

To be noted is that black can also challenge the white knight by means of 9…Bd6, but that is a different story.

So it seems white has indeed a difficult time in the Ziegler position, but not because of the so called “refutation” 11…Qc7, but rather because of 11…Nb6 ( or 9…Bd6 ) Fortunately, the resulting position is really complicated and a well prepared attacker can emerge with an even game. But chances seem very small that your opponent will find this single continuation in an over-the-board game, with the clock ticking away.

Monday, June 4, 2012

O'Kelly variation - 7...Bg5 Nbd7 line.

Stefan Bucker focused in 2010 on on some potential lines in the O'Kelly ( or Ziegler ) defense. I elaborated them in my book "Attack with the Blackmar Diemer".

After 1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 c6 5.Bc4 exf3 6.Nxf3 Bf5, Stefan suggested to play 7.Bg5 (diagram).

Today, we will consider the most natural continuation : 7...Nbd7 8.Qe2 e6 9.000 (diagram)

Houdini now suggests 9...Be7 as the strongest move, after which white prepares the breaktrough in the centre with the surprising 10.Bxf6 (diagram).

a/ 10...Bxf6 11.d5
...a1/ 11...cxd5 12.Nxd5 (=)
...a2/ 11...Bxc3 12.dxe6 (=)
...a3/ 11...00 12.dxe6 (+=)
...a4/ 11...Qe7 12.dxe6 (in my book, I sugested 12.d6, but 12...Qd8 is better for black)
......a4a/ 12...fxe6 13.Ne4 (=)
......a4b/ 12...Bxe6 13.Bxe6 (=)
...a5/ 11...Qc7 12.dxe6 fxe6 13.Bxe6 (+=)

b/ 10...Nxf6 11.Ne5
...b1/ 11...Nd5 12.g4 (=) (improving on 12.Nxd5 I wrote earlier)
...b2/ 11...00 12.g4 (+=)
...b3/ 11...Qc7 12.g4 (=)
...b4/ 11...Qb6 12.g4 (+=)
...b5/ 11...Qa5 12.g4 (+=)
...b6/ 11...h6 12.Rhf1 (=)
...b7/ 11...h5 12.h3 (=) (I evaluated this earlier as better for black, but it seems this is equal)
...b8/ 11...Nd7 12.Nxd7 Qxd7 13.d5 (+=)

c/ 10...gxf6 11.Re1
...c1/ 11...Rg8 12.h3 (=) (much better than 12.g3 I suggested in my book)
...c2/ 11...Qc7 12.d5 (+=)
...c3/ 11...Qb6 12.Nh4 (+=)
...c4/ 11...Qb6 12.d5 (+=)
...c5/ 11...Bg6 12.Bxe6 fxe6 13.Qxe6 (=)
...c6/ 11...Bg4 12.d5 (=)
...c7/ 11...Bb4 12.Nh4 (=)
...c8/ 11...Bd6 12.d5 (+=)
...c9/ 11...Nb6 12.d5 (=)

So it seems there is not a single line that gives black an advantage in this so called "refutation" of the Blackmar Diemer gambit ! Guess the critics will have to find another line to prove our beloved opening is refuted.