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Play 3NT How do make a plan?

#1 User is offline   Winstonm 

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Posted 2018-June-04, 15:29

Opening lead is the club 3. (3rd and 5th leads.) <br><br>There are 5 top tricks, 3 diamonds and 2 clubs. If the opponents' diamonds are divided 3-3, we can win 4 diamond tricks. As we have no chance unless the diamonds are divided that way, we assume that it is so. That still leaves us 3 tricks short. The only place to find 2 additional tricks is the heart suit. How should we tackle the heart suit to give us the best chance to develop 3 heart tricks?

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#2 User is offline   NickRW 

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Posted 2018-June-05, 02:28

Are they playing 4th best leads?
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#3 User is offline   Winstonm 

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Posted 2018-June-05, 08:58

View PostNickRW, on 2018-June-05, 02:28, said:

Are they playing 4th best leads?



No, sorry, 3rd and 5th. Assume 5-3 club break. I also need to change the spades, as I meant this to be a novice/beginner's hand emphasizing strictly the heart suit.
"Injustice anywhere is a threat to justice everywhere." Black Lives Matter. / "I need ammunition, not a ride." Zelensky
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#4 User is offline   Winstonm 

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Posted 2018-June-05, 09:07

Note change to spade suit: QJx instead of Kxx.
"Injustice anywhere is a threat to justice everywhere." Black Lives Matter. / "I need ammunition, not a ride." Zelensky
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#5 User is offline   apollo1201 

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Posted 2018-June-05, 13:30

Was quite complex otherwise indeed. Anyway I still believe it is more of a I&A.
We have to guess who had Ax or hope of a 33-split ❤️. The ❤️9 complexifies too as we can finesse for the 10.
As we can’t play twice towards KQ due to lack of entries (unless’East ducks’with Axx and he would fool many good players), and I understand W is longer in the suit he led so shorter in ❤️, we can try small to J and’small both hands if J wins. That is specifically playing for this layout and no hanky-panky from E.
The finesse is theoretically 50% while 3-3 break is 36%. A bit less due the already known assymetry in a side suit.
Well...that is hard!
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#6 User is offline   Winstonm 

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Posted 2018-June-05, 19:52

View Postapollo1201, on 2018-June-05, 13:30, said:

Was quite complex otherwise indeed. Anyway I still believe it is more of a I&A.
We have to guess who had Ax or hope of a 33-split ❤️. The ❤️9 complexifies too as we can finesse for the 10.
As we can’t play twice towards KQ due to lack of entries (unless’East ducks’with Axx and he would fool many good players), and I understand W is longer in the suit he led so shorter in ❤️, we can try small to J and’small both hands if J wins. That is specifically playing for this layout and no hanky-panky from E.
The finesse is theoretically 50% while 3-3 break is 36%. A bit less due the already known assymetry in a side suit.
Well...that is hard!


This is the heart of the matter - the finesse of the 9 is another way of playing the combination.
"Injustice anywhere is a threat to justice everywhere." Black Lives Matter. / "I need ammunition, not a ride." Zelensky
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#7 User is offline   Stephen Tu 

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Posted 2018-June-06, 02:08

I think it's way, way closer than you guys are implying. Playing for the drop in hearts has significant extra chances in finding singleton and doubleton T's; hearts don't have to be 3-3 for drop to work, someone might have Tx or AT. If you are certain that East has 5 cd suit, then finesse is better by a little, but with 4 cd suit the drop is quite a bit better. East might lead 3 from ??32 ?
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#8 User is offline   Winstonm 

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Posted 2018-June-06, 12:52

View PostStephen Tu, on 2018-June-06, 02:08, said:

I think it's way, way closer than you guys are implying. Playing for the drop in hearts has significant extra chances in finding singleton and doubleton T's; hearts don't have to be 3-3 for drop to work, someone might have Tx or AT. If you are certain that East has 5 cd suit, then finesse is better by a little, but with 4 cd suit the drop is quite a bit better. East might lead 3 from ??32 ?


Stephen - there is the additional factor of the hand shapes mirroring. I know. Factor in single 10 and doubleton 10 and low to the Jack and low back gives the best chance of 3 heart tricks. But try to construct a novice//beginner hand sometime. I was looking for baby steps first. (Did you happen to notice the 9? How does that change the chances?)

Btw, your point is excellent and goes along with the point of the lesson, i.e., to get beginners into the habit of looking more deeply into positions that may look routine. Thank you for your input.
"Injustice anywhere is a threat to justice everywhere." Black Lives Matter. / "I need ammunition, not a ride." Zelensky
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#9 User is offline   johnu 

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Posted 2018-June-06, 14:22

View Postapollo1201, on 2018-June-05, 13:30, said:

and I understand W is longer in the suit he led so shorter in ❤️, we can try small to J and’small both hands if J wins. That is specifically playing for this layout and no hanky-panky from E.


OP made North the declarer instead of the traditional South, so East was the opening leader, not West. East is more likely to have led from 5 clubs on this auction and if so, West is more likely to have longer hearts.
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#10 User is offline   apollo1201 

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Posted 2018-June-06, 15:34

View Postjohnu, on 2018-June-06, 14:22, said:

OP made North the declarer instead of the traditional South, so East was the opening leader, not West.

Oh yes. So if I even missed the truly N&B part of the problem that was, before the ❤️, telling dummy from declarer...
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#11 User is offline   johnu 

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Posted 2018-June-07, 03:31

View PostStephen Tu, on 2018-June-06, 02:08, said:

I think it's way, way closer than you guys are implying. Playing for the drop in hearts has significant extra chances in finding singleton and doubleton T's; hearts don't have to be 3-3 for drop to work, someone might have Tx or AT. If you are certain that East has 5 cd suit, then finesse is better by a little, but with 4 cd suit the drop is quite a bit better. East might lead 3 from ??32 ?


For those interested in doing their own calculations, use Richard Pavlicek's Suit Break Calculator,

http://rpbridge.net/cgi-bin/xsb2.pl

e.g.

Set vacant spaces for West to 10 (assuming West has 3 clubs), and East to 8 (assuming East led from 5 clubs)

Set missing cards to 6 for the unknown 6 hearts

Press Calculate

You should get these results.

 West 10 spaces       Missing 6 Cards       East 8 spaces 

West	East	Ways	SpecificGeneric	Group
3	3	20	1.81	36.20	36.20
4	2	15	2.11	31.67	48.64
2	4	15	1.13	16.97
5	1	6	1.81	10.86	13.88
1	5	6	0.50	3.02
6	0	1	1.13	1.13	1.28
0	6	1	0.15	0.15
21	21	64	 8.65	100.00	100.00


Playing for 3-3 hearts or the 10 to drop, the odds are calculated as

3-3 break - 36.2%
4-2 break - 1/3 of 31.67% have a doubleton 10
2-4 break - 1/3 of 16.97% have a doubleton 10
5-1 break - 1/6 of 10.86% have a singleton 10
1-5 break - 1/6 of 3.02% have a singleton 10
1-5 break - 1/6 of 3.02% have a singleton A (if you lead low to J, the ace will pop up and you have 3 heart tricks)
6-0 break - 100% of 1.13% (if you lead a high heart, East will show out and you can take a heart finesse)

Only 1 of the last 2 cases can be handled. If you start with a high heart from hand, you can pick up the 6-0 break, but the 1-5 break with singleton ace will lose to the ace, and you only have 2 heart tricks. If you start with a low heart from hand, you can pick up a singleton ace with West, but won't know to take a 1st round finesse against the 10.

The 1-5 break with singleton ace happens .5% (=1/6 * 3.02%) when is less than the 1.13% chance of a 6-0 break, so playing a high heart from hand is better.

Add up the percentages for all the possible breaks to get a total success percentage.


For the line depending on a finesse for 10, do similar calculations for each of the distributions assuming you are going to finesse West.
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#12 User is offline   Phil 

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Posted 2018-June-11, 06:11

1. We played the cJ at T1, right?
2. Seems more likely West led from 5 instead of 3.
3. Finessing is only necessary when west has h)Txxx. Tx is popping up. West might have overcalled with ATxxx and a spade card. Does not seem close.
4. Since we need diamonds 33 (probably), hooking gets even thinner, requiring wrst to be 1435. Yes, 3433 comes into play.
5. Maybe the key takeaway for n00bs is not ruining our entries and cashing diamonds first.
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