[Dirk Kuijt]

I think it is something like this

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North, unaccountably misses the stone code 7NT, and ends in 7♠, Fortunately, spades break and 7♠ is cold. Switching the Spade Ace and deuce and North is in big trouble.

[PFormaini]

Dirk Kuijt, on Jan 24 2010, 11:24 PM, said:

I think it is something like this

           <!-- FULLHAND begin --><table border=1> <tr> <td> <table> <tr> <td>Dealer:</td> <td> ????? </td> </tr> <tr> <td>Vul:</td> <td> ???? </td> </tr> <tr> <td>Scoring:</td> <td> Unknown </td> </tr> </table> </td> <td> <table> <tr> <th> </th> <th> <table> <tr> <th class='spades'>♠</th> <td> AKQJ </td> </tr> <tr> <th class='hearts'>♥</th> <td> AKQJ </td> </tr> <tr> <th class='diamonds'>♦</th> <td> AKQJ </td> </tr> <tr> <th class='clubs'>♣</th> <td> A </td> </tr> </table> </th> <th> </th> </tr> <tr> <th> <table> <tr> <th class='spades'>♠</th> <td> 5432 </td> </tr> <tr> <th class='hearts'>♥</th> <td>  </td> </tr> <tr> <th class='diamonds'>♦</th> <td>  </td> </tr> <tr> <th class='clubs'>♣</th> <td> KQJT98765 </td> </tr> </table> </th> <th> </th> <th> <table> <tr> <th class='spades'>♠</th> <td> T987 </td> </tr> <tr> <th class='hearts'>♥</th> <td> T987 </td> </tr> <tr> <th class='diamonds'>♦</th> <td> T987 </td> </tr> <tr> <th class='clubs'>♣</th> <td> 2 </td> </tr> </table> </th> </tr> <tr> <th> </th> <th> <table> <tr> <th class='spades'>♠</th> <td> 6 </td> </tr> <tr> <th class='hearts'>♥</th> <td> 65432 </td> </tr> <tr> <th class='diamonds'>♦</th> <td> 65432 </td> </tr> <tr> <th class='clubs'>♣</th> <td> 43 </td> </tr> </table> </th> <th> </th> </tr> </table> </td> <td>  </td> </tr> </table><!-- FULLHAND end -->

North, unaccountably misses the stone code 7NT, and ends in 7♠,  Fortunately, spades break and 7♠ is cold.  Switching the Spade Ace and deuce and North is in big trouble.

No.

How, exactly, do EAST-WEST make 10 tricks with SPADES as trump after that switch?

They don't.

Plus - SOUTH plays the hand. After this switch, WEST either leads a trump, whereafter SOUTH can pull trumps and win the rest, or else leads a CLUB, where Soth wins dummy's ACe of clubs and at least 3 more tricks, totaling at least 4.

[655321]

bb79, on Jan 24 2010, 08:33 PM, said:

cayuga strikes again


gwnn
what op says is you made 13 in 1, down 10 next one so 13- (-10) =23
just like if you were down 1, there were 14 trick swing

Hey, this is fun:

We are in 7 on a finesse:

• Setup 1: The King is onside, we make 13 tricks.
  
• Setup 2: The King is also onside, again we make 13 tricks.

With no change in the cards, we have achieved a swing of 13 tricks!

[jdonn]

Cayuga is back!

So if I am south, I make 13 tricks on one layout, but switching a card my opponents make 1 trick, how many tricks were swung? 1, 2, or 14? Gwnn what's that math problem website again?

[gwnn]

One hand I took 10 tricks. The other table -LOL- EW took 3!!!! That's a THIRTEEN trick swing!!! (I was S).

(don't claim to have written something original here bcos Mbodell 655 and jdonn also wrote similar stuff but it is still funny)

[PFormaini]

jdonn, on Jan 25 2010, 02:11 AM, said:

Cayuga is back!

So if I am south, I make 13 tricks on one layout, but switching a card my opponents make 1 trick, how many tricks were swung? 1, 2, or 14? Gwnn what's that math problem website again?

Gwnn:

No. In layout 1, N-S are cold for 13 tricks with SPADES as trump against any lead or defense. After switching the 1 card between N and W, (the other 50 cards remaining the same). E-W can now take the first 10 tricks with SPADES as trump.

Not sure how much clearer the instructions can be made without resorting to hand puppets.

[TimG]

PFormaini, on Jan 24 2010, 08:12 PM, said:

That is a 23 trick swing from N-S tp E-W - all after a simple exchange of a single card from N to W.

Leaving north with 12 cards and west with 14? Or are you proposing that two cards move?

[Cyberyeti]

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7♠ makes trivially on any defence.

Now swap N's ace of trumps with W's ♥10.

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A heart lead overtaken and 3 rounds of spades would appear to hold declarer to 2 tricks.

The hint makes this more difficult

[dellache]

PFormaini, on Jan 25 2010, 01:12 AM, said:

gwnn, on Jan 24 2010, 07:09 PM, said:

um sorry for nitpicking but looks like it's just a 10 trick swing. who is declarer?

No.

It is a 23 trick swing.

In case 1 - N-S take all 13 tricks.

In case 2 - E-W take 10 tricks.

That is a 23 trick swing from N-S tp E-W - all after a simple exchange of a single card from N to W.

What you suggest is not a 23 trick(s) swing. This is actually a 3 tricks swing. This is so obvious that I don't understand why you won't agree with me.

Let me paraphrase what you say :

In case 1 - E-W take 0 trick.
In case 2 - N-S take 3 tricks.

0 + 3 = 3 (I'm not talking about differences but about total tricks ? ok ?)
That is a 3 trick swing from E-W to N-S all after a simple exchange of a single card from W to N .

Moreover, I don't understand why you put the limit at 3 tricks for NS, when it's so obvious to find a case for going from 13 to **2** :

---

South makes 13 tricks on any lead with Spades as trump.
Exchange ♠Ace and ♥5, and the defence now makes 11 tricks.
(is that a 24 tricks or a 2 tricks swing ? Ouch, I've lost focus again...).

But real puzzle lovers will of course see a case for a 25 tricks swing.