Monday, March 16, 2009

Quagmire


In "Chess For Tigers", Simon Webb delineates a small food chain with tigers near the top predator, rabbits below, and heffalumps/elephants above. Since I'm into Scrabble these days, I'm a little more into word origins. As far as I can tell, "heffalump" originates from A.A. Milne's use of it in Winnie the Pooh stories as a kind of kids' corrupted pronunciation of elephant like "pasgetti" is to "spaghetti".


Perhaps this rabbit-tiger-heffalump food chain is standard knowledge in the UK as I previously was only familiar with the more boring shark/fish terminology. A few weeks ago, I blogged about a game in which I cast myself as the tiger and my class B opponent as the rabbit. In this game, I'm going to recast myself as the heffalump and my class B opponent as the tiger.

The opening was a rehash of a treatment of the Accelerated Dragon that my opponent and I discussed three months ago. In that game, he played a slow attack on the queenside and I decided to directly clash with him in that sector. Eventually, I won a pawn and then wore him down. In this game, he played the book moves a little longer and again we clashed on the queenside. In the middlegame complications, I believe I obtained an advantage and went for a combination that should have won material, but I overlooked several zwischenzugs in the main line and in the many side variations. What do you get when you throw a bunch of zwischenzugs into a conflict? Quagmire. My current judgment is that the tactical execution of the combination was only enough for equality and that I should have built up the pressure a bit longer in my usual boring positional style. Here is the position in question:


My last move was Qd3-e3 threatening Bb6 forking or at least cramping Black. Black just moved Nf6-d7 to defend b6. I immediately noticed that this blocks the escape of the bishop on c6 which I have the opportunity to take advantage of with b3-b4-b5. However, after 17.b4, Black has 17...Ra3!? pinning my knight, which doesn't necessarily stop b5 from being effective. But then I noticed that my bishop on d4 has its own mobility problems because Qe3 blocked its retreat. Black can take advantage of this in the line 17.b4 e5! 18.bxa5? exd4 Qe2 dxc3 and now White is losing. So I eventually decided that Bxg7 was necessary, but after Kxg7, Black has an additional resource of Qb6 and if the queens exchange, the knight arrives at b6 attacking my c4 bishop which became loose after Qe3 and b4. With the king on g7, I thought I could get a tempo in any combination by playing Qd4+ getting out of a pin from Ra3, but then the annoying e5 comes again and I have to move my queen. In this combination, if my queen abandons the g1-a7 diagonal, Black's queen can enter with Qb6+ and perhaps win the b pawn. So any line with Qd4+ e5 Qxd6 Qb6+ began to look unattractive. At this point I couldn't hold everything in my mind any more and decided to play 17.Bxg7 Kxg7 18.b4 and deal with the position at that point.



After the game, a spectator suggested that after 17.Bxg7 Kxg7 18.b4 Ra8?! 19.b5 Qb6, I should have played 20.Nd1 to rehabilitate my combination. If 20...Qxe3, 21.Nxe3 defends the loose bishop on c4 so that 21.Nb6 bxc6 is winning. It sounded good, but Fritz tells me that 20...Ra3 would have forced a similar outcome to the actual game.

At the end of my combination, I had this position:


It was pretty clear to me that 22.cxb7 Ra7 23.Rfb1 Rb8 was darn near equal, so I thought long about 22.c7 and the question, is it weak or strong? My analysis was polluted with fantasy variations here as I tried to work in the series Nd5 e6 Nb6 forking two rooks on a8 and c8. Ultimately, I decided that c7 Rfc8 Nb5 would be my variation and if the c7 pawn became untenable, I would try really hard to win the b7 pawn in return. Well, as you can see in the replay, c7 was a mistake that just left me down a pawn in a double rook endgame. My opponent played fairly well in the early endgame, maintaining an active king and an active rook. I think my opponent really did have winning chances for most of the first half of the endgame. But he began to meander and then blundered horribly. In the following position, my opponent played Rc4?? which gave away all of his advantage and then some. My endgame experience told me immediately that my passed a-pawn was an advantage. I spent the rest of the game counting and recounting the steps to the win.



Incidentally, Fritz seemed to fail me at two junctures in analyzing this game afterward. In the first diagram, Fritz never seems to let go that the b4-b5 line isn't that good. And in the pawns endgame, the move horizon is too far for it to see that the win is inevitable.

Chess For Tigers is a cute book with practical advice and some games, but the advice almost falls into the Duh! category of advice. In chapter 5 on "How to catch Rabbits", the main points are 1. Keep it simple, 2. Don't take unnecessary risks, 3. Don't overpress, 4. Have patience that your opponent will compound his mistakes. One quote that struck me is "It is always possible that he [opponent] will know a good line against your favorite sharp opening, or that you will end up by bamboozling yourself in the cut-and-thrust of a wild position."

In chapter 6 on "How to trap Heffalumps", the main points are 1. Head for a complicated position and hope that he makes a serious mistake before you do, 2. Play actively, 3. Randomize, 4. Complicate, and 5. Be brave. Chapter 7 is entitled, "Fortune favors the lucky: Being an initiation into the Secrets of Swindling". And Chapter 8 is "How to win won positions".

Perhaps through the unfortunate layout of the thicket of variations, I stepped into the quagmire and became trapped. Fortunately, my tiger opponent let his tail fall too close to my groping trunk and I dragged him into the muck. Using him as a stepping stone, I escaped the trap with the win and preserved my chances of qualifying for the club championship.