White 20 - Page 2

LaurV · 2014-02-09, 13:58

[QUOTE=cheesehead;366488]After [B]20 Nd4 O-O 21 Nf6+ Bxf6[/B] there is an alternative to 22 exf6:
[B]22 Rxf6[/B][/QUOTE]
That would be wrong, we lose the sente. We have to find a move to force out of them a reply. The point is they don't "have to" move the horse if we beat there with the rook. They may find another move that complicates the things. Move the h pawn to h5, or defend it with the king (Kg7, Kh7). He is also free to pursuit the queen's flank, the b/c columns, etc, the situation gets ugly. Rf8c8 is a version I didn't like too much for the case we beat with the pawn, but now this can get bad for us, if they sacrifice the pawn. Like in 22.Rxf6, Rf8c8 23.Bxh6 Nf5, 24 Bd2 (otherwise the d4 pawn is in danger, due to ...bxc3, ...Rb3), they succeed to infiltrate the horses there, and one of our rook is locked, we completely lost the sente. We still can play, the game is far away to be lost, but I don't like it.

After spending few hours this afternoon with the position, I am still thinking/agreeing that the best move is Ne4, the best path to reply for black will be with the castling, then the game goes like: 20. Ne4 O-O 21.Nf6+ Bxf6 22. exf6 Nd5 23.Bxh6 and that is our pawn.

cheesehead · 2014-02-10, 08:38

[QUOTE=cheesehead;366488]After [strike][B]20 Nd4[/strike] [/B][/QUOTE]I meant [b]20 Ne4[/b], not Nd4.

LaurV · 2014-02-10, 15:24

huh, sure, I didn't see the typo, my all thinking/comment was done for Ne4.

Now, if we agreed, we better move it..

cheesehead · 2014-02-11, 15:23

[QUOTE=LaurV;366497][QUOTE=cheesehead;366488]After [B]20 Nd4 O-O 21 Nf6+ Bxf6[/B] there is an alternative to 22 exf6:
[B]22 Rxf6[/B].[/QUOTE]
That would be wrong, we lose the sente.[/QUOTE]No, we don't. I just need to explain the motive, which I didn't take time for earlier. See below for details.

[quote]We have to find a move to force out of them a reply. The point is they don't "have to" move the horse if we beat there with the rook.[/quote]Yes, they do, or else our rook will simply waltz back to f2 to bolster our Q-side defense.

[quote]They may find another move that complicates the things. Move the h pawn to h5, or defend it with the king (Kg7, Kh7).[/quote]Black is welcome to do any of those instead of Nf5, because they have no forcing value.

[quote]He is also free to pursuit the queen's flank, the b/c columns, etc,[/quote]He's free to do that anyway; we can't prevent it with any single move. Besides, 23 Rf2 would contribute to our Q-side defense if Black hasn't played 22 ... Nf5.

I've looked at Black's chances on the b/c columns, and haven't yet found anything we can't meet adequately.

[quote]Rf8c8 is a version I didn't like too much[/quote]Why? You think Black's going to be able to push his blocked c-pawn anytime soon? No, it's going to just sit there, limiting his bishop's scope, because we have adequate control of c3.

A rook exchange on b3 might free the c4-pawn, but we have plenty of strength to stop it from promotion.

[quote]but now this can get bad for us, if they sacrifice the pawn.[/quote]Sacrifice which pawn?

[quote]Like in 22.Rxf6, Rf8c8 23.Bxh6[/quote]No, 22 Rxf6 Rfc8 [B]23 Rf2[/B]. The h6-pawn is not more important than our rook. If they waste a tempo before shutting the knight-door, we just move our rook back.

[quote]they succeed to infiltrate the horses there, and one of our rook is locked, we completely lost the sente.[/quote]No, we haven't; our position has lots of strength.

[quote]After spending few hours this afternoon with the position, I am still thinking/agreeing that the best move is Ne4, the best path to reply for black will be with the castling, then the game goes like: 20. Ne4 O-O 21.Nf6+ Bxf6 22. exf6 Nd5 23.Bxh6 and that is our pawn.[/quote]But this line (move 22 and later, not 20 Ne4) gives up our control of the d6 square. Let's not over-value short-term material gain.

Maintaining control of d6 and f6, and blocking the e6-pawn are big reasons for capturing with the rook instead of the pawn on move 22. Black's light-square bishop is seriously hemmed-in by his own pawns on c4, e6 and f7, and we have our g2 bishop to counter adventurism on the long diagonal. I do concede that a pawn on f6 blocks Black's f-pawn better than one on e6, and that control of e7/g7 may be better than control of d6/f6. OTOH, if the f-file remains half-open from our side, that's a lingering worry for Black.

cheesehead · 2014-02-11, 20:58

Actually, I forgot to write the biggest reason for [b]22 Rxf6[/b]. It's something I've been aware of for several moves.

Black's position is [i]loose[/i], with undefended and shakily defended men.

In particular, Black has weakness on rank 6.

Look at the board after we place our rook on that same rank with 22 Rf6.

Black's bishop/a6 is undefended. Black's knight/c6 is defended only by his knight/e7. Black's pawn/h6 is undefended.

If Black moves 22 ... Nf5, he adds a defender to the pawn/h6, but he removes the only defender of his other knight, which happens already to be attacked on the long light-square diagonal by our B/g2.

(Note that 22 ... Nd5 would be unfeasible precisely because after 23 Bxd5 exd5 our rook has direct access to the other Black knight: 24 Rxc6. And that, in turn, would attack the undefended B/a6.)

After 22 ... Nf5, Black has two undefended men on which rank? 6.

Where's our rook? Rank 6.

Only the pawns at e6 and g6 prevent our rook/f6 from capturing one of the defended men. But [i]nothing[/i] prevents our B/g2 from capturing the undefended N/c6 on move 23. And that would, in turn, make the B/a6 more insecure (shielded from our rook by only the e6-pawn), once we move the B/c6. Where's a handy move for that bishop? 24 Be4, attacking the blockading knight as well as removing one of the only two shields between our R/f6 and the B/a6.

[u]That[/u]'s why I'm advocating 22 Rxf6. It strikes directly at Black's major weakness.

In fact, this strike is so strong that if Black decides to get a pawn for the N/c6 that's he's going to lose, via 22 ... Nxd4 or ... Nxe5, our best move is not to retreat our rook, but to recapture with 23 Bxd4 or dxe5. Then Black can make the threatening-looking 23 ... Nf5, but our rook is vulnerable only if Black can actually attack it -- which he can't, except by using his remaining knight to attack it from d7, e8, g8 or h7 -- and he can do that only by opening (or leaving open) the door for our rook to leave.

Here's a scenario:
20 ... O-O 21 Nf6+ Bxf6 22 Rxf6 Nxe5 23 dxe5 Nf5 24 Be4 and here if Black moves anything except the knight we proceed with 25 Bxf5 gxf5 26 Rxh6 and we're a whole piece up. Or if 24 ... Kg7, then 25 Bxf5 gxf5 26 Bxh6+ snares even more material. Also, we then threaten to form a mating net by Nf2-g4-f6. Black can capture a pawn on the Q-side, but he can't promote any of his pawns fast enough to save his king.

cheesehead · 2014-02-12, 01:49

Re: loose positions

[I]Note that in contrast to Black, after 22 Rxf6 we have no undefended or shakily-defended attackable men on our side.[/I] Black could potentially have a strong square at d3 --- [I]but he has no way to get any of his pieces there to be a threat to us [/I](in contrast to our ease of posting knights on d6/f6)!

- - -

BTW, when I wrote post #15, I hadn't yet thought about all the things I discussed in Post #16. If it seems that anything I wrote in #16 contradicts anything in #15 -> disregard that part of #15. #16 is more comprehensive.

Note that when Black tries to scare us by shutting the gate on our rook with Nf5, we'll have [I]three[/I] different men to open the gate by attacking f5: our light-square bishop, our g-pawn, and our remaining knight. Black can't prevent all of those.

We have a powerful position, not a fragile one like Black's. Furthermore, attacking on the king-side, as we are, is more dangerous to Black than his queen-side attack is to us. Now, some of our advantage was given to us by Black with his now-seen-to-be-questionable moves ... b4 and ... Ba6 rather than solely through our own moves, but it is what it is anyway.

- - -

LaurV,

There have been three times earlier in this game when a move you promoted was initially not my favorite, but after looking into it thoroughly I became convinced it was best. So I take your preferences very seriously. Now, I hope to convince you that my recommendation for 22 Rxf6 will be best, if Black does what we expect on moves 20 and 21. Also, it may have shock value when we spring Rxf6 on Black then.

LaurV · 2014-02-12, 05:27

[QUOTE=cheesehead;366700]LaurV,

There have been three times earlier in this game when a move you promoted was initially not my favorite, but after looking into it thoroughly I became convinced it was best. So I take your preferences very seriously. Now, I hope to convince you that my recommendation for 22 Rxf6 will be best, if Black does what we expect on moves 20 and 21. Also, it may have shock value when we spring Rxf6 on Black then.[/QUOTE]
Too long to read, I am at job (lunch break, but still in hurry).
I will have to analyze everything you wrote in the last posts when I get home tonight. This because I also take your preferences very seriously here. No joke, I consider you the best player in our team (including myself, sorry WMH :P). For example, the Nd1 move was "your" move, which I hated :P, but it proved to be an excellent defensive move, over the game. I am more like the aggressive guy (only in chess :P) and I am sometime losing because I first think about how to cut the other guy's throat, and only at the end (or after the game, hehe) how to defend my own head.

So, give me some time to think about. I am sure they will reply with the castling, there is actually nothing better they can do now. I remember from the former analysis that they may lose heavily on other moves.

LaurV · 2014-02-12, 13:37

[QUOTE=cheesehead;366663]
Sacrifice which pawn?
<...>
No, 22 Rxf6 Rfc8 [B]23 Rf2[/B]. The h6-pawn is not more important than our rook. If they waste a tempo before shutting the knight-door, we just move our rook back.

No, we haven't; our position has lots of strength.
[/QUOTE]

I agree that our position is still strong here, and black's pieces are placed like mersenne primes, one here one there :razz:.

By "sacrifice" I mean the h6 pawn, which is tempting there, but after black Nf5 we have to lose moves to secure the bishop, and he develops pieces. However, 23.Rf2 is weaker, what do we reply to 23...Nf5 in this case? We can't bet the pawn anymore, we can move the bishop (where? c1? d2? what we do after he pushes 24...h5? how do we attach? we are forced to defend, we lost the sente) or not move the bishop (even worse, 24.Rd2, Nxe3 25 Nxe3 Bb7 and we are in for trouble on the queen flank)

[QUOTE=cheesehead;366679]In particular, Black has weakness on rank 6.
[/QUOTE]
Very well spotted. The question is how can we fructify it. You made your point very well. I understand this. Maybe Rxf6 is the best solution. I only don't like the thing that black has a "respiro" after the rook move, he is not forced to move that horse, and he may chose his own path to make our life miserable, in case we missed something.

[QUOTE]
Here's a scenario:
20 ... O-O 21 Nf6+ Bxf6 22 Rxf6 Nxe5 23 dxe5 Nf5 24 Be4 and here if Black moves anything except the knight we proceed with 25 Bxf5 gxf5 26 Rxh6 and we're a whole piece up. Or if 24 ... Kg7, then 25 Bxf5 gxf5 26 Bxh6+ snares even more material. Also, we then threaten to form a mating net by Nf2-g4-f6. Black can capture a pawn on the Q-side, but he can't promote any of his pawns fast enough to save his king.[/QUOTE]That is wonderful, except that Nxe5 will only be played in a blitz game, and only if the player is drunk. That is a terrible move for black. Why should they give a horse for free? In a game where a few people think for a week, they will play 22...Rf8c8 or 22...Kg7.

Let's see their reply to 20 first, than we can argue more, but I still see exf6 being better that Rxf6. The last has so many unknowns, in spite of the fact that it can be [U]strategically[/U] better (here you almost convinced me :P), is the [U]tactical[/U] part (or better, its unknown side) what I am afraid of.

[B][U]If[/U][/B] they play our game with 20 and 21, then either we can convince each-other for the 22, or we will have to let WMH to decide... Of course, if he does not have a better move, which we both, in our pride to fight each-other, did completely missed it :razz:

LaurV · 2014-02-12, 16:08

Hey, let's forget a little about our little dispute, and think about this:

What the hack we reply to 20...Kf8 ?

The question mark is question mark, not a "questionable move" mark. I squeezed my brain for one hour, I actually don't have a good reply to this. It is making our 20 Ne4 completely uneffective :(

(i mean, we still have the queen side attack, c5, d6, but only little of the initial dream...)

WMHalsdorf · 2014-02-12, 16:34

I expect them to delay with bxc to which the only good reply is bxc

LaurV · 2014-02-12, 16:43

20..bxc here, would not be verrrry brilliant from their side. We can ignore it, we are not forced to capture immediately: 21.Nd6 Kd7 22.Nxc3 Nf5 Nc3e4, they can not push nor take because the mate may be close there, ex: c3 24.Nc5 K somewhere, Nxa6, bad for black.

2014-02-12, 01:49	#17
cheesehead "Richard B. Woods" Aug 2002 Wisconsin USA 2²·3·641 Posts	Re: loose positions [I]Note that in contrast to Black, after 22 Rxf6 we have no undefended or shakily-defended attackable men on our side.[/I] Black could potentially have a strong square at d3 --- [I]but he has no way to get any of his pieces there to be a threat to us [/I](in contrast to our ease of posting knights on d6/f6)! - - - BTW, when I wrote post #15, I hadn't yet thought about all the things I discussed in Post #16. If it seems that anything I wrote in #16 contradicts anything in #15 -> disregard that part of #15. #16 is more comprehensive. Note that when Black tries to scare us by shutting the gate on our rook with Nf5, we'll have [I]three[/I] different men to open the gate by attacking f5: our light-square bishop, our g-pawn, and our remaining knight. Black can't prevent all of those. We have a powerful position, not a fragile one like Black's. Furthermore, attacking on the king-side, as we are, is more dangerous to Black than his queen-side attack is to us. Now, some of our advantage was given to us by Black with his now-seen-to-be-questionable moves ... b4 and ... Ba6 rather than solely through our own moves, but it is what it is anyway. - - - LaurV, There have been three times earlier in this game when a move you promoted was initially not my favorite, but after looking into it thoroughly I became convinced it was best. So I take your preferences very seriously. Now, I hope to convince you that my recommendation for 22 Rxf6 will be best, if Black does what we expect on moves 20 and 21. Also, it may have shock value when we spring Rxf6 on Black then. Last fiddled with by cheesehead on 2014-02-12 at 02:45

2014-02-12, 05:27	#18
LaurV Romulan Interpreter "name field" Jun 2011 Thailand 2⁴·643 Posts	[QUOTE=cheesehead;366700]LaurV, There have been three times earlier in this game when a move you promoted was initially not my favorite, but after looking into it thoroughly I became convinced it was best. So I take your preferences very seriously. Now, I hope to convince you that my recommendation for 22 Rxf6 will be best, if Black does what we expect on moves 20 and 21. Also, it may have shock value when we spring Rxf6 on Black then.[/QUOTE] Too long to read, I am at job (lunch break, but still in hurry). I will have to analyze everything you wrote in the last posts when I get home tonight. This because I also take your preferences very seriously here. No joke, I consider you the best player in our team (including myself, sorry WMH :P). For example, the Nd1 move was "your" move, which I hated :P, but it proved to be an excellent defensive move, over the game. I am more like the aggressive guy (only in chess :P) and I am sometime losing because I first think about how to cut the other guy's throat, and only at the end (or after the game, hehe) how to defend my own head. So, give me some time to think about. I am sure they will reply with the castling, there is actually nothing better they can do now. I remember from the former analysis that they may lose heavily on other moves. Last fiddled with by LaurV on 2014-02-12 at 05:28

2014-02-12, 13:37	#19
LaurV Romulan Interpreter "name field" Jun 2011 Thailand 2⁴×643 Posts	[QUOTE=cheesehead;366663] Sacrifice which pawn? <...> No, 22 Rxf6 Rfc8 [B]23 Rf2[/B]. The h6-pawn is not more important than our rook. If they waste a tempo before shutting the knight-door, we just move our rook back. No, we haven't; our position has lots of strength. [/QUOTE] I agree that our position is still strong here, and black's pieces are placed like mersenne primes, one here one there :razz:. By "sacrifice" I mean the h6 pawn, which is tempting there, but after black Nf5 we have to lose moves to secure the bishop, and he develops pieces. However, 23.Rf2 is weaker, what do we reply to 23...Nf5 in this case? We can't bet the pawn anymore, we can move the bishop (where? c1? d2? what we do after he pushes 24...h5? how do we attach? we are forced to defend, we lost the sente) or not move the bishop (even worse, 24.Rd2, Nxe3 25 Nxe3 Bb7 and we are in for trouble on the queen flank) [QUOTE=cheesehead;366679]In particular, Black has weakness on rank 6. [/QUOTE] Very well spotted. The question is how can we fructify it. You made your point very well. I understand this. Maybe Rxf6 is the best solution. I only don't like the thing that black has a "respiro" after the rook move, he is not forced to move that horse, and he may chose his own path to make our life miserable, in case we missed something. [QUOTE] Here's a scenario: 20 ... O-O 21 Nf6+ Bxf6 22 Rxf6 Nxe5 23 dxe5 Nf5 24 Be4 and here if Black moves anything except the knight we proceed with 25 Bxf5 gxf5 26 Rxh6 and we're a whole piece up. Or if 24 ... Kg7, then 25 Bxf5 gxf5 26 Bxh6+ snares even more material. Also, we then threaten to form a mating net by Nf2-g4-f6. Black can capture a pawn on the Q-side, but he can't promote any of his pawns fast enough to save his king.[/QUOTE]That is wonderful, except that Nxe5 will only be played in a blitz game, and only if the player is drunk. That is a terrible move for black. Why should they give a horse for free? In a game where a few people think for a week, they will play 22...Rf8c8 or 22...Kg7. Let's see their reply to 20 first, than we can argue more, but I still see exf6 being better that Rxf6. The last has so many unknowns, in spite of the fact that it can be [U]strategically[/U] better (here you almost convinced me :P), is the [U]tactical[/U] part (or better, its unknown side) what I am afraid of. [B][U]If[/U][/B] they play our game with 20 and 21, then either we can convince each-other for the 22, or we will have to let WMH to decide... Of course, if he does not have a better move, which we both, in our pride to fight each-other, did completely missed it :razz: Last fiddled with by LaurV on 2014-02-12 at 13:47

2014-02-12, 16:08	#20
LaurV Romulan Interpreter "name field" Jun 2011 Thailand 2⁴×643 Posts	Hey, let's forget a little about our little dispute, and think about this: What the hack we reply to 20...Kf8 ? The question mark is question mark, not a "questionable move" mark. I squeezed my brain for one hour, I actually don't have a good reply to this. It is making our 20 Ne4 completely uneffective :( (i mean, we still have the queen side attack, c5, d6, but only little of the initial dream...) Last fiddled with by LaurV on 2014-02-12 at 16:16

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2014-02-09, 13:58	#12
LaurV Romulan Interpreter "name field" Jun 2011 Thailand 2⁴·643 Posts	[QUOTE=cheesehead;366488]After [B]20 Nd4 O-O 21 Nf6+ Bxf6[/B] there is an alternative to 22 exf6: [B]22 Rxf6[/B][/QUOTE] That would be wrong, we lose the sente. We have to find a move to force out of them a reply. The point is they don't "have to" move the horse if we beat there with the rook. They may find another move that complicates the things. Move the h pawn to h5, or defend it with the king (Kg7, Kh7). He is also free to pursuit the queen's flank, the b/c columns, etc, the situation gets ugly. Rf8c8 is a version I didn't like too much for the case we beat with the pawn, but now this can get bad for us, if they sacrifice the pawn. Like in 22.Rxf6, Rf8c8 23.Bxh6 Nf5, 24 Bd2 (otherwise the d4 pawn is in danger, due to ...bxc3, ...Rb3), they succeed to infiltrate the horses there, and one of our rook is locked, we completely lost the sente. We still can play, the game is far away to be lost, but I don't like it. After spending few hours this afternoon with the position, I am still thinking/agreeing that the best move is Ne4, the best path to reply for black will be with the castling, then the game goes like: 20. Ne4 O-O 21.Nf6+ Bxf6 22. exf6 Nd5 23.Bxh6 and that is our pawn.

2014-02-10, 08:38	#13
cheesehead "Richard B. Woods" Aug 2002 Wisconsin USA 1E0C₁₆ Posts	[QUOTE=cheesehead;366488]After [strike][B]20 Nd4[/strike] [/B][/QUOTE]I meant [b]20 Ne4[/b], not Nd4.

2014-02-10, 15:24	#14
LaurV Romulan Interpreter "name field" Jun 2011 Thailand 2830₁₆ Posts	huh, sure, I didn't see the typo, my all thinking/comment was done for Ne4. Now, if we agreed, we better move it..

2014-02-11, 15:23	#15
cheesehead "Richard B. Woods" Aug 2002 Wisconsin USA 2²·3·641 Posts	[QUOTE=LaurV;366497][QUOTE=cheesehead;366488]After [B]20 Nd4 O-O 21 Nf6+ Bxf6[/B] there is an alternative to 22 exf6: [B]22 Rxf6[/B].[/QUOTE] That would be wrong, we lose the sente.[/QUOTE]No, we don't. I just need to explain the motive, which I didn't take time for earlier. See below for details. [quote]We have to find a move to force out of them a reply. The point is they don't "have to" move the horse if we beat there with the rook.[/quote]Yes, they do, or else our rook will simply waltz back to f2 to bolster our Q-side defense. [quote]They may find another move that complicates the things. Move the h pawn to h5, or defend it with the king (Kg7, Kh7).[/quote]Black is welcome to do any of those instead of Nf5, because they have no forcing value. [quote]He is also free to pursuit the queen's flank, the b/c columns, etc,[/quote]He's free to do that anyway; we can't prevent it with any single move. Besides, 23 Rf2 would contribute to our Q-side defense if Black hasn't played 22 ... Nf5. I've looked at Black's chances on the b/c columns, and haven't yet found anything we can't meet adequately. [quote]Rf8c8 is a version I didn't like too much[/quote]Why? You think Black's going to be able to push his blocked c-pawn anytime soon? No, it's going to just sit there, limiting his bishop's scope, because we have adequate control of c3. A rook exchange on b3 might free the c4-pawn, but we have plenty of strength to stop it from promotion. [quote]but now this can get bad for us, if they sacrifice the pawn.[/quote]Sacrifice which pawn? [quote]Like in 22.Rxf6, Rf8c8 23.Bxh6[/quote]No, 22 Rxf6 Rfc8 [B]23 Rf2[/B]. The h6-pawn is not more important than our rook. If they waste a tempo before shutting the knight-door, we just move our rook back. [quote]they succeed to infiltrate the horses there, and one of our rook is locked, we completely lost the sente.[/quote]No, we haven't; our position has lots of strength. [quote]After spending few hours this afternoon with the position, I am still thinking/agreeing that the best move is Ne4, the best path to reply for black will be with the castling, then the game goes like: 20. Ne4 O-O 21.Nf6+ Bxf6 22. exf6 Nd5 23.Bxh6 and that is our pawn.[/quote]But this line (move 22 and later, not 20 Ne4) gives up our control of the d6 square. Let's not over-value short-term material gain. Maintaining control of d6 and f6, and blocking the e6-pawn are big reasons for capturing with the rook instead of the pawn on move 22. Black's light-square bishop is seriously hemmed-in by his own pawns on c4, e6 and f7, and we have our g2 bishop to counter adventurism on the long diagonal. I do concede that a pawn on f6 blocks Black's f-pawn better than one on e6, and that control of e7/g7 may be better than control of d6/f6. OTOH, if the f-file remains half-open from our side, that's a lingering worry for Black. Last fiddled with by cheesehead on 2014-02-11 at 15:45

2014-02-11, 20:58	#16
cheesehead "Richard B. Woods" Aug 2002 Wisconsin USA 2²×3×641 Posts	Actually, I forgot to write the biggest reason for [b]22 Rxf6[/b]. It's something I've been aware of for several moves. Black's position is [i]loose[/i], with undefended and shakily defended men. In particular, Black has weakness on rank 6. Look at the board after we place our rook on that same rank with 22 Rf6. Black's bishop/a6 is undefended. Black's knight/c6 is defended only by his knight/e7. Black's pawn/h6 is undefended. If Black moves 22 ... Nf5, he adds a defender to the pawn/h6, but he removes the only defender of his other knight, which happens already to be attacked on the long light-square diagonal by our B/g2. (Note that 22 ... Nd5 would be unfeasible precisely because after 23 Bxd5 exd5 our rook has direct access to the other Black knight: 24 Rxc6. And that, in turn, would attack the undefended B/a6.) After 22 ... Nf5, Black has two undefended men on which rank? 6. Where's our rook? Rank 6. Only the pawns at e6 and g6 prevent our rook/f6 from capturing one of the defended men. But [i]nothing[/i] prevents our B/g2 from capturing the undefended N/c6 on move 23. And that would, in turn, make the B/a6 more insecure (shielded from our rook by only the e6-pawn), once we move the B/c6. Where's a handy move for that bishop? 24 Be4, attacking the blockading knight as well as removing one of the only two shields between our R/f6 and the B/a6. [u]That[/u]'s why I'm advocating 22 Rxf6. It strikes directly at Black's major weakness. In fact, this strike is so strong that if Black decides to get a pawn for the N/c6 that's he's going to lose, via 22 ... Nxd4 or ... Nxe5, our best move is not to retreat our rook, but to recapture with 23 Bxd4 or dxe5. Then Black can make the threatening-looking 23 ... Nf5, but our rook is vulnerable only if Black can actually attack it -- which he can't, except by using his remaining knight to attack it from d7, e8, g8 or h7 -- and he can do that only by opening (or leaving open) the door for our rook to leave. Here's a scenario: 20 ... O-O 21 Nf6+ Bxf6 22 Rxf6 Nxe5 23 dxe5 Nf5 24 Be4 and here if Black moves anything except the knight we proceed with 25 Bxf5 gxf5 26 Rxh6 and we're a whole piece up. Or if 24 ... Kg7, then 25 Bxf5 gxf5 26 Bxh6+ snares even more material. Also, we then threaten to form a mating net by Nf2-g4-f6. Black can capture a pawn on the Q-side, but he can't promote any of his pawns fast enough to save his king.

2014-02-12, 16:34	#21
WMHalsdorf Feb 2005 Bristol, CT 1001₈ Posts	I expect them to delay with bxc to which the only good reply is bxc

2014-02-12, 16:43	#22
LaurV Romulan Interpreter "name field" Jun 2011 Thailand 2⁴·643 Posts	20..bxc here, would not be verrrry brilliant from their side. We can ignore it, we are not forced to capture immediately: 21.Nd6 Kd7 22.Nxc3 Nf5 Nc3e4, they can not push nor take because the mate may be close there, ex: c3 24.Nc5 K somewhere, Nxa6, bad for black.