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deep_blue
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2015 Move 13g
« on: Dec 26th, 2015, 9:29am »
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I was so free to open a new thread and move this to here:
 
on Dec 26th, 2015, 8:42am, half_integer wrote:
In our discussion, we only identified one silver reply to this move (12s Cd7 Rc7 Hb7 Mb6) so I think we can work on the next Gold reply.
 
The only piece that can protect the a6 horse is our camel, put on c5 or d6.  d6 doesn't appear desirable as it quickly leads to camel loss or various frames.  Mc5 alone is not good as it allows silver Mb5 Ed5 in one move which leads to immediate camel loss (Hb6 is false protection and the silver camel pull cannot be blocked).  To prevent that 13s I see two measures: pull the d6 dog with Mc5:Dd5 which allows Ed6 in 4 steps, or put a piece on b5, where Ra5b5 is the only one that can reach.  This latter move leaves us two free steps which we can debate below.
 
The wild-card move would be to not defend the horse and play for a rapid elephant rotation, with Mf5 or Me4.  There may be some moves with the same goal which do not use all four steps for the camel this move (though Me5 is not one of them: Dd5 E:Me6 is immediate camel-for-horse trade).
 
It is important to note that the camel-for-horse trade may be inevitable, at least in the lines where we defend c6, so rather than always reject lines with camel loss for horse sacrifice, we should determine if we can protect the a6 horse or get greater compensation.  Conversely, if we cannot protect the a6 horse long term then making progress now by not defending it becomes attractive.
 
So, an updated tree (SM notation only to save typing):
 
12g ::Hf3
12s Cd7 Rc7 Hb7 Mb6
13g
    1 Md6:Dc6
    - 1.1 Dc5 Ed5 (Hf3x) - indefensible camel loss with horse hostage
 
    2 Md6:De6
    - 2.1 Ed5 (Hf3x) Mb5
    - - 2.1.1 Ec5
    - - - 2.1.1.1 De7 Cg7 Df7 Hb6 - f6 cannot be defended but maybe a camel trade can be threatened?
    - - - - 2.1.1.1.1 E::Mb3
    - - - - - 2.1.1.1.1.1 Ec4::M
    - - - - - - 2.1.1.1.1.1.1 (E/R) Md5 Dd3 - and we seem to have freed our camel and gotten a camel hostage after two more moves?
    - - - - 2.1.1.1.2 E:Mb4 (Dd3 Hg4)
    - - - - - 2.1.1.1.2.1 Ec4::M - and our camel seems to have escaped
    - - - - - 2.1.1.1.2.2 Ec4 Ma4 X - our camel escapes here too
    - 2.2 Ed5 (Hf3x) X  
    - - 2.2.1 Dc5
    - - - 2.2.1.1 E:Mc6 X X - camel loss is unavoidable
    - - 2.2.2 Ec5
    - - - 2.2.2.1 E:Mc6 X X - this frame looks like an easy elephant rotation for silver, though we are up a horse in the short term
    - - - 2.2.2.2 De7 Cg7 Df7 X - f6 cannot be defended, but this time it is harder to make camel threats in response
 
    3 Mc5 X X X
    - 3.1 Ed5 (Hf3x) Mb5 - camel is indefensible and we still have a horse hostaged
 
    4 Mc5:Dd5 - note I didn't find any really bad responses to this yet
    - 4.1 Ed4 (Hf3x) Dd6 Ed5
    - - 4.1.1 Ec4 Mb5 - doesn't appear profitable for silver, he gets a horse trade at best
    - 4.2 Ed4 (Hf3x) De5 Ed5
    - - 4.2.1 Ec4 Mb5 - still just a horse trade for silver
    - 4.3 Ec4 (Hf3x) Mb5
    - - 4.3.1 Ed6
    - - - 4.3.1.1 E:Mc6 Mb6 X - this frame looks difficult but not impossible to rotate, so this position might be OK for gold (up a horse for a camel frame)
    - - - 4.3.1.2 E:Mc6 Hb6 Ra7b7
    - - - - 4.3.1.2.1 Ha7 M:Ha6 X - a strange little position which might leave the silver camel as strongest free piece but also gives gold access to the back ranks in the west
    - - - 4.3.1.3 is there an even better silver move?
    - 4.4 Ec4 (Hf3x) Cd6
    - - 4.4.1 Rb5 M:De5 X - silver seems to get the horse and rabbit at c6 but it looks like gold's camel can always escape
 
This has taken a while so I'm going to edit in more later.
    5 Mc5 Rb5 X X - to be expanded
    6 Mf5 / Me4 / Md4 X / Md5 X X / Mc4 X X - lots of work to do here
 
I noticed that I'm almost exclusively focused on the silver moves which sacrifice the framed horse; there is the possibility of silver responses which defend but don't try for a trade.  

« Last Edit: Dec 29th, 2015, 2:42am by deep_blue » IP Logged
Hippo
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Re: 2015 Move 13g
« Reply #1 on: Dec 26th, 2015, 7:48pm »
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I don't like holding frame f3 horse with camel f4. In that case our elephant is restricted to be around f6 for most of the time to prevent Mh trade. Holding such frame and be Horse down would be really bad.
 
Actually I was thinking only about Mc5 Rb5 x x.
 
BTW: I cannot see how to play Mc5 Dd5 move.
« Last Edit: Dec 26th, 2015, 7:54pm by Hippo » IP Logged

SilverMitt
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Re: 2015 Move 13g
« Reply #2 on: Dec 28th, 2015, 3:57pm »
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By the way, silver has played the expected 12s.  I don't actually like any move with Mc5 strategically now.  I was wondering whether we should consider a move like 13g Ed5 gh5.
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half_integer
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Re: 2015 Move 13g
« Reply #3 on: Dec 28th, 2015, 7:10pm »
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Deep, somehow you quoted an older version of that post.  A reload in the 12g thread should show the update.  When I have time to add lines I'll probably repost the whole thing here.  (Do others find this tree too thorough?)
 
Hippo, Mc5:Dd5 would be the four steps Meew ds
 
I hadn't worked all the lines to add to the tree yet, but I'm liking the idea of Mc5 Rb5 and then, when silver moves his camel south, fleeing east to threaten the rotation.  It may be possible to keep silver in a catch-22 where he can't threaten both the horse and the camel at the same time, and we get free steps in the meantime.  The biggest worry is that silver could change the situation around f6 enough to prevent the camel coming across safely.  For instance, instead of M:Ra5 Hb6 Rcb7 he could play M:Ra5 Dfe6 X allowing single-move capture of a camel on f5.  There are a lot of possibilities to consider though.
 
I'm against giving up the frame voluntarily, but if we move the elephant I think it should be Ec5 since this threatens the camel pull immediately.  Another outlier move would be creating a goal threat in the east to reduce silver's free steps.  I'm not sure how something like Rh5 Hg5 Mc5 would work out - silver's horse is partly blockaded in the southeast.
 
I'm working this week so it might be a while before I explore a lot of lines.
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SilverMitt
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Re: 2015 Move 13g
« Reply #4 on: Dec 29th, 2015, 3:58am »
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I don't actually think that the pull threat following 13g Ec5 is that strong, and silver could just capture the g5 rabbit (possibly with just a prosaic 13s H:gf5) rather than race in attacking f3, in which case we seem behind.
 
But we can force silver to play 3 steps to make up for the gh5 step, while we work on breaking the horse hostage.  Silver's best plan might still be to win the rabbit, but if instead the attack on f3 comes, that would be more enjoyable practically than just losing a rabbit and winding up with a deadlocked west afterwards.
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Hippo
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Re: 2015 Move 13g
« Reply #5 on: Dec 29th, 2015, 5:45am »
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What is wrong with Mc5 Rb5 Rh5 Rh1? Or with Ms5 Rb5 x y in general?
What would be the best x, y?
 
... With the Dd5 confusion ... I am used to use capital letters just for gold. When convention to use them for both gold and silver started?
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Re: 2015 Move 13g
« Reply #6 on: Dec 29th, 2015, 6:20am »
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on Dec 29th, 2015, 5:45am, Hippo wrote:
What is wrong with Mc5 Rb5 Rh5 Rh1? Or with Ms5 Rb5 x y in general?
What would be the best x, y?
 
... With the Dd5 confusion ... I am used to use capital letters just for gold. When convention to use them for both gold and silver started?

In SilverMitt notation, the convention as I understand it is that all piece names are capitalized, but pieces of the nonmoving side are only and exactly those appearing after a : in a term. Mc5:Dd5 on a gold move is taken to mean gold camel moves to c5, while pushing or pulling a silver dog to d5 somehow.
« Last Edit: Dec 29th, 2015, 6:21am by clyring » IP Logged



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Re: 2015 Move 13g
« Reply #7 on: Dec 29th, 2015, 12:29pm »
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Quote:
I don't actually like any move with Mc5 strategically now. I was wondering whether we should consider a move like 13g Ed5 gh5.

 
We don't actually have to play gh5 to protect the horse if we play Ed5. If silver took the horse on 13g we would take the camel on 14g. This would allow us to play Rg5e instead.
 
Quote:
I hadn't worked all the lines to add to the tree yet, but I'm liking the idea of Mc5 Rb5 and then, when silver moves his camel south, fleeing east to threaten the rotation.

 
Why would silver want to move the camel south when it is holding a good hostage?
« Last Edit: Dec 29th, 2015, 12:29pm by Hufflepup » IP Logged
half_integer
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Re: 2015 Move 13g
« Reply #8 on: Dec 29th, 2015, 7:44pm »
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I see that Ed5 Rh5 effectively protects the a6 horse, but how do we respond to something like 13s Df6e4 Hf4?  It doesn't look like the f3 trap can be held without the elephant returning, in which case we've just wasted steps, but maybe you see a better path through that trap fight.  I suppose 14g Ee4:Dd4 Mc5?
 
Hufflepup: "Why would silver want to move the camel south when it is holding a good hostage?" - see line 3.1.  Playing 13s Mb5:Ra5 with our camel on c5 sets up a similar indefensible camel-for-horse trade if we don't act proactively (it just takes one extra step because of the rabbit on b5), and rabbit on a5 keeps our horse from escaping still.
 
I do see the same weakness Hippo pointed out for rotating the camel to f4; I will not explore these lines unless someone thinks this is a good long-term tradeoff.
 
So, along with the dog pull to d5, I think that Mc5 Rb5 X X is still the leading contender (though we have to be careful).  What are the most useful remaining two steps?  I see the value in Rh5; I'd also like to put Rd1 which strengthens our ability to keep pieces off d4 and e4 (though, if we don't see a line with camel or horse there, this could be deferred).  At the same time, I'd like to get the a2 or b1 rabbits at least one step closer to b3 and eventually the c6 fight.  Finally, moving the g1 rabbit will need to be done eventually as well.
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Re: 2015 Move 13g
« Reply #9 on: Dec 31st, 2015, 3:09am »
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Well, 13g Ed5 gh5 13s Dfe4 Hf4 14g Mb3 Eb5 looks okay for us.  13s Hf4 E:Hh3 may be quite strong, though, enough to make me think that giving up the g5 rabbit is better than any alternative here.
 
If we do play Mc5+ab5 on 13g, one thing to worry about the silver camel coming to b5 is that it may look to go to a5 next.  Also, it is actually quite difficult to retreat our camel safely.  We'd need to put a dog on d4 along with the camel on c4.
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deep_blue
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Re: 2015 Move 13g
« Reply #10 on: Jan 1st, 2016, 11:24am »
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Anyone wants to play some other move than those mentioned? I'll try to start a (first) poll tomorrow morning (though with the option of "more discussion").
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Re: 2015 Move 13g
« Reply #11 on: Jan 1st, 2016, 1:07pm »
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Quote:
13s Hf4 E:Hh3 may be quite strong, though, enough to make me think that giving up the g5 rabbit is better than any alternative here.
 

 
I would be surprised if Sharp was willing to decentralise the elephant so much. We should be all right with something like:
 
14g: De2n Ed5w Mb5s Mb4s
14s: hf4s Cf2w hf3s df6s
 
The camel can move across to take the horse hostage, and as soon as the situation arounf the trap is stabilised we can flip out the camel on the opposite wing.
 
If silver pushed the horse north instead on 13s then
14g: Ed5w De2n Mdb5s mb4e Would lead to a horse excange, however our follow up threats to the camel look better.
 
Quote:
If we do play Mc5+ab5 on 13g, one thing to worry about the silver camel coming to b5 is that it may look to go to a5 next.  Also, it is actually quite difficult to retreat our camel safely.  We'd need to put a dog on d4 along with the camel on c4.

 
The camel could be retreated with
14g: Mc5e Md5s Ef4w Md4s
 
But this will almost certainly lead to a horse for horse and rabbit in Sharps favour.
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SilverMitt
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Re: 2015 Move 13g
« Reply #12 on: Jan 2nd, 2016, 2:31am »
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So, it looks to me that a 13g with Mc5+ab5 is just untenable when answered with a 13s including M:ba5.  Silver doesn't necessarily have to play the Hb6+cb7 steps to force us to retreat the camel, and so the tactics should wind up favoring silver, either being able to improve while we have to spend all our steps to parry threats, or just winning material outright.
 
If we do decide to bring our elephant to free the hostage, then we are committed to it, so silver can and should decentralize the elephant if the goal is to attack around f3; otherwise our g3 horse can hold things for a while.  Then, we can't afford a rabbit step to save our rabbit, and it might be better on g5 if something were to get flipped to f5, as well.
 
Thus, I am now in favor of 13g Ec5 and I hope silver cannot win more than a rabbit immediately.
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half_integer
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Re: 2015 Move 13g
« Reply #13 on: Jan 2nd, 2016, 7:42am »
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I thought you were in favor of Ed5 Rh5, not Ec5.  When did the former get refuted, or you decided the latter was stronger?
 
And what is the overall thinking on Mc5:Dd5?  I'd like to have the free steps of the simpler Mc5 Rb5, but I didn't find a fatal flaw to the fight after this move.
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half_integer
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Re: 2015 Move 13g
« Reply #14 on: Jan 2nd, 2016, 5:23pm »
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SilverMitt, I'd still like to hear more of your thoughts on what happens after 13g Mc5 Rb5 X X 13s M:Ra5 X X - maybe there are alternate Gold moves to follow up.
 
Have you considered 14g Eb4, attacking the silver camel when it advances?  This also provides avenues to free the gold camel from the anticipated attack.
 
Maybe you still don't consider this ideal - we each get two free steps and we're more decentralized, but the armies are about equal in distribution on the board.
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