Wednesday, February 08, 2017

Stay away from the LoAs

Sometimes you have to defuse an assault on your own king. I seem to have a special talent to let my monarch flea to the wrong square. Which underpins the notion that my subconscience must know something about chess, since if it would move randomly, I would sometimes flea to the right square by chance.

Diagram 1. White to move

q1R5/p2Q4/p4k2/8/4b3/P7/1P3P1P/2q3K1 w - - 0 1
[solution]

The critical position is reached in the following diagram. Where should the white king find a refuge?

Diagram 2. Stay away from the LoAs
I thought it is important to stay away from the PoP (Point of Pressure) f3, where the black queen and the black bishop converge. So I dared not to move to e2. But this is position is not about mate, but about getting the rook. The white king must stay away from the two LoAs (Lines of Attack) against the white rook. For black it is paramount that the queen stays into contact with both LoAs all the time. Which means it must stay on the g-file. And again a seemingly complex position is simplified by the PLF (PoPLoAFun) system.

2 comments:

  1. 2164.8 - Very S-L-O-W to finally get the solution on this one - I kept getting interrupted and it took a lot of time (more than 30 minutes actual "solving" time). I also have horrible difficulties working with open positions with Queens and lots of potential checks. Queen endings have always given me fits - too darn many things to keep in mind!

    An interesting tête–à–tête between the White King and the Black Queen! I find it amusing that the basic King maneuver is a triangulation maneuver (based on Zugzwang). I certainly did NOT "see" THAT coming in the initial position!

    My initial thought was to try for some kind of exchange, perhaps of the Rook for the Bishop, given that White is ahead (effectively) by three Pawns. But, as open as the board is AND with Queens on board, that seemed like it could be problematic for avoiding a draw by perpetual check. But, as you noted, as long as the Black Queen can check along the g-file, that is a faint hope. So the question becomes: how can White force Black to move the Black Queen off of that crucial g-file?

    The white squares provide one possible "escape hatch." With the White King on e2, the Black Bishop cannot check on f3 without allowing the White King to escape via d3 (while avoiding the c1-h6 diagonal like the plague). (THAT took a LONG time to "see"!) So the Black Bishop has the Function of preventing the White King from escaping along the diagonal f1-c4. There's the first critical pointer toward the solution.

    By eliminating the move by the Black Bishop, only a check by the Black Queen on f3 is left, which removes the Black Queen from contact with the crucial g-file, especially the g5-square, IFF the White King can move without getting stuck on one of the LoAs. But, after the Black Queen gives check on f3, the White King CAN step on to one of the LoAs (g1-c1) without the White Rook getting "electrocuted" (skewered). Black gets one more spite check on h1, and then the lights go out because the power (check on g5) has been turned off. White gains a crucial tempo to do something to gain the initiative.

    Most assuredly, the PoPLoAFun approach is broadly applicable for reducing the work required to "see" the contours of a specific position! Without it, I doubt that I would have even attempted to solve such a puzzle! I would have taken one "look" at it and decided it was too far beyond my capabilities.

    I have been very encouraged by the results of this process of "looking" with the vulture's eye view at the PoPLoAFun "road kill"!

    Just for giggles, after solving it by myself, I gave the diagram 2 position to GM Stockfish for a look at alternatives, because I thought that Bf3+ "might" be somewhat better (although still losing eventually). Sure enough, he thinks 1. Ke2! Bf3+ (+7.43) is better than 1. ... Qf3+ (+9.51). My gut feeling is that Black wants to keep as much hardware on board as possible, even though that looks hopeless. Once the "tricks" are over and White gains the initiative, it's only "a matter of technique." I wish I were confidant that I had that necessary skill of technique! Alas, I am reasonably certain I would royally screw up the subsequent play.



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  2. I have done this level of problems before. Under the adage that if I want to become 2100 player, I must solve 2100 rated problems. First doing it slow, later becoming faster. It usually took me hours to solve this kind of puzzles with T&E (Trial and Error)in a way that the position looked simple (search for "slapped my head" in my blog). Then I tried to ingrain the patterns of the position into my brain. To no avail, since it were the wrong patterns. Before you can learn something from this position, you must unearth the relevant patterns. Which are not physical but virtual, only visible with the minds eye.

    I never derived much satisfaction from my T&E approach. With the PLF (PoPLoAFun) approach, I find it very satisfying though, once the "truth of the position starts dawning". The first step must be to make the PLF approach so familiar that it becomes the preferred habit. I don't want to be bothered by not knowing many things of the assault and the promotion motif too much. YET. PLF first.

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