[Cascade]

The hand in this thread http://forums.bridgebase.com/index.php?sho...ndpost&p=482848

got me wondering.

What are the normal expert standard rules for when a card at trick one is suit preference when a singleton comes in the dummy?

Marshall Miles (Defensive Carding) and others that I have read have argued that it should still be attitude in many situations - assuming a fairly standard Attitude, Count, Suit Preference order of priorities for carding.

[aguahombre]

Dunno what is expert standard, just know what some of us use, and what I would guess with an unfamiliar pard.

Assuming 3rd hand has several choices:

highest that can be afforded=sp for highest of two switch choices.
Lowest=lowest suit
In-between=might as well continue the suit unless you have an obvious switch.

[Cascade]

I am more interested in when suit preference applies. I think I know how to use suit preference when it applies.

Does the singleton in dummy automatically mean you are playing suit preference?

[aguahombre]

Yes, I think so ---- but, as stated ----obscenely high or absolutely lowest is the application. So maybe the answer is yes and no.

[bluecalm]

Whatever method you choose you should be able to show A or K in clubs.
We use suit preference. Some people use obvious shift. The difference is that playing suit preference you have an option of dropping middle card which you should be very careful with though. It's better to signal the suit which isn't the most important than drop a card which can be misread.

[awm]

"Obvious shift" carding basically solves this problem. As usual when partner leads, with UDA:

(1) High suggests a shift to the "obvious" alternative suit
(2) An honor suggests a shift to the other alternative suit
(3) Low encourages continuation, or certainly denies interest in the "obvious" alternative suit

[bluecalm]

I think playing obvious shift and suit preference is basically the same. You just use different cards to show the same things.

[jdonn]

bluecalm, on Aug 2 2010, 12:48 AM, said:

I think playing obvious shift and suit preference is basically the same. You just use different cards to show the same things.

Yes I have argued this before. Not playing obvious shift, in standard carding,

(1) High encourages continuation, or certainly denies interest in the "obvious" alternative suit
(2) An honor suggests a shift to the other alternative suit
(3) Low suggests a shift to the "obvious" alternative suit

I've never had it explained to me how obvious shift solves anything.

[awm]

The priorities here are different. Ignore for the moment the part about playing an honor card, as much of the time you will not have one available. The problem is that you have two signals available (high card or low card) to distinguish three alternatives. This means you can clearly signal for one option, but there is some ambiguity in the others. Assuming standard carding:

(1) Attitude. High card clearly says continue. Low card is ambiguous as to which of the other two suits you should switch to.

(2) Suit preference (assuming you play high for continuation also). Low card clearly says switch to lower suit. High card is ambiguous between continue and switch to higher suit.

(3) Obvious shift. Low card clearly says switch to "obvious shift" suit. High card is ambiguous between continue and switch to the "non-obvious" suit.

The point is that the three options are not equally likely. Often either continuing or switching to the "non-obvious" suit is simply illogical, and can be eliminated based on the dummy and the auction. For this reason, obvious shift most often will give an unambiguous signal.

Thus the "standard" approach to carding involves swapping between attitude and suit preference signals based upon what you think is illogical or what you think partner needs to know. This is why standard signals say "signal suit preference if dummy has a singleton" whereas normally you signal attitude. As long as you and partner agree as to what you're signaling, there's no problem (other than the necessary ambiguity as above). However, I have seen instances where members of a partnership disagree as to what the signal should mean. For example, suppose partner leads something and I really want him to switch to the higher outstanding suit. If we're signaling attitude, I must play a low card (high card would be continue) and then hope partner gets it right. But if we're signaling suit preference, I must play a high card (a low card would be the worst possible choice). You can see that a disaster will result if partner and I disagree as to what I'm supposed to be signaling. Obvious shift has two advantages here. First, the type of signal doesn't vary based on the hand except by very formalized rules determining the "obvious shift." So there's no worry about which types of signals we play. Of course, there is still the inherent ambiguity of the signal (when I play a high card) but the "obvious shift" suit rules are defined to minimize these ambiguities. And at least resolving the ambiguity is based on partner thinking about the hand (can continuing be right?) rather than thinking about what sort of signal I am giving.

[jdonn]

awm, on Aug 2 2010, 01:53 AM, said:

(1) Attitude. High card clearly says continue. Low card is ambiguous as to which of the other two suits you should switch to.

(2) Suit preference (assuming you play high for continuation also). Low card clearly says switch to lower suit. High card is ambiguous between continue and switch to higher suit.

(3) Obvious shift. Low card clearly says switch to "obvious shift" suit. High card is ambiguous between continue and switch to the "non-obvious" suit.

The point is that the three options are not equally likely. Often either continuing or switching to the "non-obvious" suit is simply illogical, and can be eliminated based on the dummy and the auction. For this reason, obvious shift most often will give an unambiguous signal.

Playing standard signals, if continuing is obviously illogical then by normal signaling rules it becomes a suit preference situation. High asks for the higher switch, low asks for the lower switch.

Playing standard signals, if a switch to a particular side suit is obviously illogical then high asks for a continuation and low asks for a switch to the other side suit.

Playing either standard signals or obvious shift signals, if either a continuation or either switch looks possible then no signal will get partner to switch to the non-obvious shift suit.

I still see absolutely no advantage, with the exception of obvious shift having a set of formalized rules as you say. But I don't see this as an advantage to that method, it's just an advantage to having discussed your methods, which people who play standard signals should do as well.

[whereagles]

Cascade, on Aug 2 2010, 03:25 AM, said:

Does the singleton in dummy automatically mean you are playing suit preference?

Not for me at least. You may want to encourage pard to play into the ruff so as to shorten dummy's entries.

My rule for SP when dummy comes up with sing/void is:
- Dummy has 4+ trumps.
- They are playing in a known 9 card fit.

Under these conditions, 3rd seat's card is SP.

[cherdanno]

I think it's a common agreement. Maybe "SP unless it looks like we may want to force dummy" is also a common one. In any case, when you have 5+cards it's obviously convenient to play SP as you can request a continuation with a middle card.

[pooltuna]

Cascade, on Aug 1 2010, 10:25 PM, said:

I am more interested in when suit preference applies. I think I know how to use suit preference when it applies.

Does the singleton in dummy automatically mean you are playing suit preference?

basically I would think suit preference would kick in when the side suits clearly signal impending and immediate disaster

[Phil]

I think SP applies only when we partner knows or can infer that we have a few cards to signal with (at least 4?) by our bidding or we know partner can infer it.

Cherdanno said:

Maybe "SP unless it looks like we may want to force dummy" is also a common one.

The problem here is it may be difficult for partner to be on this wavelength and know whether or not to force dummy.

So, assuming we have length (and partner knows this), high and low cards are SP, and a middle card is 'continue' or 'no preference'. Frankly, I thought this was standard Kantar.

[Fluffy]

and then you might often want to switch to trumps to prevent dummy from ruffing too many.

[Cascade]

cherdanno, on Aug 2 2010, 09:48 PM, said:

when you have 5+cards it's obviously convenient to play SP as you can request a continuation with a middle card

... provided partner knows you have 5+ cards.

[awm]

Scoring: MP

---

The auction (E/W silent) was 1♥-1♠-3♠-4♠. West on lead selected the diamond ace, hoping to cash out before the minor suit tricks disappear on the hearts. E/W play UDCA.

Looking at the dummy, it appears obvious that we should switch to clubs. On a lucky day, partner will have the ♣K and we will score three tricks this way when any other play is likely to hold us to just the two aces. On a really lucky day, partner might have a spade trick also and we can set.

How are we going to read partner's card at trick one? It seems reasonable that a high card from partner will be UDA, telling us to stop playing diamonds and play clubs. Perhaps partner thinks a diamond continuation (hoping to promote a trump) is vaguely reasonable from our side, whereas a heart play is obviously ridiculous, so he should discourage to make sure we don't try for a trump promotion. On the other hand, a low card from partner seems like it could be suit preference. Continuing diamonds does seem rather silly, and perhaps partner looking at doubleton heart thinks we might just play him for singleton and switch to hearts. Dummy having Kx after the ace lead is almost like dummy having a singleton after all, where we certainly do play suit preference.

So it seems quite possible that whatever card East plays will be viewed as a signal to switch to clubs. Sometimes this is okay, since a club switch is the most likely "right play" on the hand. But suppose it is one of those rare hands where East really does want a diamond continuation (say he has two little and some trump honors) or a heart switch (say he has a void in hearts). Now he effectively can't signal for it at all, and whatever he does (barring illegal tempo games) will get him a club switch!

I agree that if we have formal rules for all situations as to whether the trick one signal is attitude or suit preference, and these rules are designed in such a way that we are almost always giving the signal which is most useful of the two, then standard carding methods are roughly equivalent to obvious shift. After all, this is what obvious shift gives you -- a formal method for determining what partner's signal means which depends on the situation in such a way that partner's signal is usually as useful as possible. However, the vast majority of players using standard (or UDCA) signals do not have such discussions, and are frequently on a guess as to what signal partner needs/expects/will find useful. When there are misunderstandings, it can be costly.

[eyhung]

Recent Bridge World had a letter about this issue. The writer thinks that the general rule should be :

suit preference should apply when 3rd hand is known to have 5+ cards in the suit.

Otherwise attitude/count applies.

[Cascade]

awm, on Aug 3 2010, 08:18 AM, said:

where we certainly do play suit preference

This is the information that I wanted from this thread.

Is this really how everyone plays.

Another point on your hand while a heart is silly from our side partner does not necessarily know that we know that a heart is silly - we could have more hearts and a heart void possible. Actually even here some players bid spades with four card heart support looking for the perfect 4=4 fit or some other reason so a heart void is possible with partner.

[gnasher]

A heart switch could well be right on awm's hand - declarer might have three of them, so we could give partner a ruff after winning ♠A.

In my partnerships, we have the rule that an attitude signal nearly always relates to the holding in the suit led, and if your attitude is known you signal count or suit preference, whichever seems more sensible. On this hand suit preference is obviously more sensible.