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Encrypted leads? England UK

#1 User is offline   bluejak 

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  Posted 2010-June-04, 18:10

EBU Orange book 2006 rev 2009 said:

11 R 2 Encrypted carding

No agreement is permitted whereby the meaning of a lead, signal or discard is based in principle on information not available to declarer, so no form of ‘encrypted’ carding is permitted.

For those who do not understand encrypted signalling, the simplest example is where declarer is known to be playing an eight-card fit, perhaps because of Stayman. Now the defender with an odd number of trumps plays standard signals, and the one with an even number of trumps plays reverse signals. Both defenders know what they are doing, but declarer does not know until part way through the hand. Such signals are not permitted in EBU, WBU, ACBL, EBL or WBF events, I believe.

Now, a correspondent asks:

I noticed that some of the Italians play a lead style of
Low = odd with an honour or even without an honour
High = odd without an honour and even with an honour
 
Is that legal here?


Are these leads encrypted?
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#2 User is offline   nigel_k 

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Posted 2010-June-04, 19:41

Surely they meant "information available to partner but not declarer" because the regulation is absurd if interpreted literally.

So I would say the given example is legal because partner doesn't have any particular information, unavailable to declarer, that enables him to work out what the leader has.
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#3 User is offline   mrdct 

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Posted 2010-June-04, 20:47

My understanding of the ban on encrypted signals is that it is illegal to encrypt based on information known to both defenders and not known to declarer. In the opening leading methods described, the basis of the encryption is only known to the person who lead. Both declarer and the other defender have just as much chance to work out what's going on. I believe the Italian methods are completely legal.
Disclaimer: The above post may be a half-baked sarcastic rant intended to stimulate discussion and it does not necessarily coincide with my own views on this topic.
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#4 User is offline   Cyberyeti 

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Posted 2010-June-05, 01:46

mrdct, on Jun 4 2010, 09:47 PM, said:

My understanding of the ban on encrypted signals is that it is illegal to encrypt based on information known to both defenders and not known to declarer. In the opening leading methods described, the basis of the encryption is only known to the person who lead. Both declarer and the other defender have just as much chance to work out what's going on. I believe the Italian methods are completely legal.

Interesting question.

More to the point is:

Does the information have to be guaranteed to be available to defenders without any reference to what's in the leader's partner's hand and not declarer, or is it considered encrypted simply if it's quite likely.

Eg Dummy decks with KJxx in a suit, the man sitting over has AQ10, both defenders know his partner has no higher honour and hence the count, but declarer doesn't.
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#5 User is offline   paulg 

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Posted 2010-June-05, 03:09

The WBF Systems Policy is more explicit:

players may not use signalling methods by which the message or messages conveyed by the signals are hidden from the declarer because of some key available only to the defenders (i.e. encrypted signals are not allowed)

I have always assumed that the EBU used the same principle.
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#6 User is offline   pooltuna 

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Posted 2010-June-05, 07:57

nigel_k, on Jun 4 2010, 08:41 PM, said:

Surely they meant "information available to partner but not declarer" because the regulation is absurd if interpreted literally.

So I would say the given example is legal because partner doesn't have any particular information, unavailable to declarer, that enables him to work out what the leader has.

not sure David's example is all that great either as it implies that 1NT is called explicitly without a 5 card major otherwise the encrypted opening lead would be probabilistic in nature. Personally I find this particular rule among the most onerous of those currently in use.
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#7 User is offline   kfay 

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Posted 2010-June-05, 08:24

So what if the opps play some sort of system where declarer has relayed their shape and you make these leads and....
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#8 User is offline   jdonn 

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Posted 2010-June-05, 08:29

I agree with the first two replies. A literal interpretation of the definition makes no sense (no information about my hand is available to declarer) so common sense tells us if declarer has just as fair of a shot to know what's going on as the partner of the leader then the lead should be allowed.
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#9 User is offline   peachy 

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Posted 2010-June-05, 11:18

I have tried to read and re-read the question. Or rather, to re-read and understand why somebody asked David to answer the question. The lead agreement is not encrypted, declarer has as much chance as opening leader's partner to figure it out later, although not necessarily at the time the lead is made. But that is true of any systemic lead, the information about the suit length and honor location surfaces gradually.
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#10 User is offline   bluejak 

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  Posted 2010-June-05, 14:49

pooltuna, on Jun 5 2010, 02:57 PM, said:

not sure David's example is all that great either as it implies that 1NT is called explicitly without a 5 card major otherwise the encrypted opening lead would be probabilistic in nature.

It is an example to make it clear, not a ruling. Ok, the pair concerned never have a 5-card major - ok?
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#11 User is offline   dburn 

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Posted 2010-June-05, 15:10

bluejak, on Jun 4 2010, 07:10 PM, said:

EBU Orange book 2006 rev 2009 said:

11 R 2 Encrypted carding

No agreement is permitted whereby the meaning of a lead, signal or discard is based in principle on information not available to declarer, so no form of ‘encrypted’ carding is permitted.

For those who do not understand encrypted signalling, the simplest example is where declarer is known to be playing an eight-card fit, perhaps because of Stayman. Now the defender with an odd number of trumps plays standard signals, and the one with an even number of trumps plays reverse signals. Both defenders know what they are doing, but declarer does not know until part way through the hand. Such signals are not permitted in EBU, WBU, ACBL, EBL or WBF events, I believe.

Now, a correspondent asks:

I noticed that some of the Italians play a lead style of
Low = odd with an honour or even without an honour
High = odd without an honour and even with an honour
 
Is that legal here?


Are these leads encrypted?

Shouldn't think so, any more than "second best without an honour, fourth best with an honour" leads are encrypted.

In both cases, leader's partner does not automatically know when he sees the lead what kind of suit the leader has. Sure, he may know because of what he can see in his hand and the dummy, and the declarer may not know, but this does not matter.

The essence of an encrypted lead or signal is that it is based on some key possessed (or assumed to be possessed) by the defenders but not by declarer before the play is made. In other words, each defender knows what message is intended by the card played, but the declarer does not know (and cannot tell until he has played a few more tricks to establish the key, by which time it may be too late).

Of course, the banning of such signals is further evidence that the game of bridge should in the view of the fossils who currently play it be permitted - nay, encouraged - to fossilize. But that is a separate issue.
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#12 User is offline   OleBerg 

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Posted 2010-July-01, 05:40

I was reading this thread:

http://forums.bridge...showtopic=40075

In his reply, gnasher suggests that a spade discount from partner would be count.

That gave me a peculiar thought:

What if I didn't hold the A; wouldn't it make sense to see a spade partners discard as encouraging/discouraging?

And if it does, are we not playing encrypted signals?
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#13 User is offline   Cascade 

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Posted 2010-July-01, 14:37

OleBerg, on Jul 1 2010, 11:40 PM, said:

I was reading this thread:

http://forums.bridge...showtopic=40075

In his reply, gnasher suggests that a spade discount from partner would be count.

That gave me a peculiar thought:

What if I didn't hold the A; wouldn't it make sense to see a spade partners discard as encouraging/discouraging?

And if it does, are we not playing encrypted signals?

Seems to be encrypted to me.

Your signal depends on the possession or lack of possession of the ace.
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#14 User is offline   blackshoe 

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Posted 2010-July-01, 14:54

How is partner supposed to know whether you have the A? Or is the assumption that declarer can't have it?
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#15 User is offline   Cascade 

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Posted 2010-July-01, 15:39

Obviously it is case by case.

There will certainly be hands where it is known that declarer does not have the ace. That case is the most clear that the signals are encrypted (or at least could be).

There are many other situations where it is common for defensive signals to be 'what partner needs to know'. Some of these will be based on information that is available to the defenders and not to declarer. It seems from the definition these then become illegal encrypted agreements.
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#16 User is offline   bluejak 

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  Posted 2010-July-02, 08:03

Suppose dummy has KQJxxx and no other card above a seven and the contract is 3NT. Declarer wins the opening lead and plays on dummy's suit. Now, two things are completely obvious to a competent pair of defenders. First, it is very important for the defender without the ace to signal count so that his partner will take his ace at the correct time. Second, it is of supreme unimportance for the defender with the ace to show count, so Smith is much more useful. Such a signalling arrangement seems both encrypted and common-sense.

The EBU thought so anyway, which is why we have:

EBU Orange book said:

11 R 2 Encrypted carding

No agreement is permitted whereby the meaning of a lead, signal or discard is based in principle on information not available to declarer, so no form of ‘encrypted’ carding is permitted.

Exceptionally an agreement arises typically where dummy has a long suit missing the Ace, and no outside entry, and involves the defender with the Ace of the suit giving a signal along Smith Peter lines, ie a signal concerning another suit, while the defender without the Ace gives a count signal. As a specific exception to the ban on encrypted signals, a count signal is permitted in place of a Smith Peter in specifically-defined situations provided that the use of the method is fully disclosed.

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#17 User is offline   gnasher 

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Posted 2010-July-02, 16:27

Does this exception apply only when dummy's missing card is the ace?

If dummy has AQJ109 and declarer takes a finesse, it's normal for West's signals to vary according to whether he has the king. Without the king, West should signal count. Holding the king, West might want to give suit preference or Smith (although he might also choose to signal reverse count for deceptive reasons).
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#18 User is offline   gwnn 

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Posted 2010-July-02, 16:32

Doesn't the law say "typically where" ?
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#19 User is offline   jdonn 

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Posted 2010-July-02, 18:41

gwnn, on Jul 2 2010, 05:32 PM, said:

Doesn't the law say "typically where" ?

The important line seems to be:

Quote

As a specific exception to the ban on encrypted signals, a count signal is permitted in place of a Smith Peter in specifically-defined situations provided that the use of the method is fully disclosed.

To me that says you can, by agreement, substitute a count signal for a smith or suit preference signal in any situation you want, as long as you have specifically defined each situation and fully disclose the method. The long suit missing the ace in an entry-less dummy is merely an example (ergo "typically") but no situation at all (in which you would otherwise play a suit preference type of signal) is ruled out.
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#20 User is offline   jeremy69 

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Posted 2010-July-03, 03:26

It ws certainly the intention of the L&E that any position where there was a potentially entryless dummy was ok i.e. not just a missing Ace was required.
Of course if you know that this is what your opponents do then you may be able to play towrds KQJxxx with Axx and get a signal which might be of help to you.
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