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Leads

#21 User is offline   barmar 

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Posted 2016-August-09, 08:45

View Postrhm, on 2016-August-09, 03:29, said:

This is often claimed and rarely underpinned by arguments.

The most obvious argument is that you have to make this decision with the least information. The opening leader only knows what's in his own hand and what he can infer from the auction. After that, you can see an additional 13 cards in dummy, a huge increase in information. And then you get signals from partner and can make inferences from declarer's play.

#22 User is offline   helene_t 

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Posted 2016-August-09, 09:51

Leads are difficult in the sense that a lot of guesswork is needed.

But they are easy in the sense that if you follow a few principles you will rarely make a demonstrably bad choice.

Compare to 12th tricks discards. A competent defender will rarely get it wrong but most of us will sometimes have lost count. And whenever you do make the wrong discard it will usually be demonstrably wrong
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#23 User is offline   rhm 

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Posted 2016-August-09, 10:03

View Postbarmar, on 2016-August-09, 08:45, said:

The most obvious argument is that you have to make this decision with the least information. The opening leader only knows what's in his own hand and what he can infer from the auction. After that, you can see an additional 13 cards in dummy, a huge increase in information. And then you get signals from partner and can make inferences from declarer's play.

The argument maybe obvious but is weak.
I can see how lack of information increases guesswork, but lack of information does not make a decision more difficult.

Rainer Herrmann
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#24 User is offline   1eyedjack 

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Posted 2016-August-09, 10:14

You can choose, if you wish, to apply a very simple set of self-imposed "rules" to take away or resolve the guesswork in an opening lead. Having done so, you will not find leading very difficult. You may not be very successful, but at least the difficulty is eliminated.
Psych (pron. saik): A gross and deliberate misstatement of honour strength and/or suit length. Expressly permitted under Law 73E but forbidden contrary to that law by Acol club tourneys.

Psyche (pron. sahy-kee): The human soul, spirit or mind (derived, personification thereof, beloved of Eros, Greek myth).
Masterminding (pron. mPosted ImagesPosted ImagetPosted Imager-mPosted ImagendPosted Imageing) tr. v. - Any bid made by bridge player with which partner disagrees.

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#25 User is offline   nullve 

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Posted 2016-August-09, 11:33

View Post1eyedjack, on 2016-August-09, 10:14, said:

You can choose, if you wish, to apply a very simple set of self-imposed "rules" to take away or resolve the guesswork in an opening lead. Having done so, you will not find leading very difficult. You may not be very successful, but at least the difficulty is eliminated.

I don't think anyone can justify their lead by saying

"I led x because condition C held"

unless they're prepared to believe that the rule

"If condition C holds, lead x."

is a good one.
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#26 User is offline   1eyedjack 

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Posted 2016-August-09, 12:58

Or ... They lack the imagination, intellect, or inclination to consider and adopt a more complex but more accurate set of conditions than condition C in resolving to lead x, perhaps because to do so would be "difficult".
Psych (pron. saik): A gross and deliberate misstatement of honour strength and/or suit length. Expressly permitted under Law 73E but forbidden contrary to that law by Acol club tourneys.

Psyche (pron. sahy-kee): The human soul, spirit or mind (derived, personification thereof, beloved of Eros, Greek myth).
Masterminding (pron. mPosted ImagesPosted ImagetPosted Imager-mPosted ImagendPosted Imageing) tr. v. - Any bid made by bridge player with which partner disagrees.

"Gentlemen, when the barrage lifts." 9th battalion, King's own Yorkshire light infantry,
2000 years earlier: "morituri te salutant"

"I will be with you, whatever". Blair to Bush, precursor to invasion of Iraq
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#27 User is offline   barmar 

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Posted 2016-August-10, 08:49

View Postrhm, on 2016-August-09, 10:03, said:

The argument maybe obvious but is weak.
I can see how lack of information increases guesswork, but lack of information does not make a decision more difficult.

Maybe we're talking about different things. My understanding is that what's usually claimed is that making a good opening lead is difficult. It's often phrased as "more tricks are lost on the opening lead than any other part of the game." That doesn't mean that the decision process is more difficult than other parts of the game, but that making the best decision is more difficult.

For instance, if you have a suit headed by AK, or a singleton (especially in your partner's suit), it's often a no-brainer to lead it. Most of the time it will be the most effective lead, or at least not blow anything. But not always. Now switch to situations where the lead isn't so obvious, it's much more likely that your lead will be poor.

#28 User is offline   1eyedjack 

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Posted 2016-August-10, 13:30

I would put it slightly differently but it may amount to the same thing.

There are undoubtedly cases where the long term trick expectation of two different leads, on the available information, is sufficiently close to equal that for all practical purposes it is a straight 50:50 toss-up. In those occasions the process of a mental coin toss is a very simple process with a moderate 50% success expectation. It would be wrong on those occasions to attribute the low success rate to a "difficulty" in opening lead.

On the other hand there will be a lot of other hands where the disparity, if properly analysed, is significant, but it could be no easy task to arrive reliably at that conclusion, just as it may not be easy to establish with confidence that it is a straight coin toss on those occasions when it genuinely is so.
Psych (pron. saik): A gross and deliberate misstatement of honour strength and/or suit length. Expressly permitted under Law 73E but forbidden contrary to that law by Acol club tourneys.

Psyche (pron. sahy-kee): The human soul, spirit or mind (derived, personification thereof, beloved of Eros, Greek myth).
Masterminding (pron. mPosted ImagesPosted ImagetPosted Imager-mPosted ImagendPosted Imageing) tr. v. - Any bid made by bridge player with which partner disagrees.

"Gentlemen, when the barrage lifts." 9th battalion, King's own Yorkshire light infantry,
2000 years earlier: "morituri te salutant"

"I will be with you, whatever". Blair to Bush, precursor to invasion of Iraq
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#29 User is offline   rmnka447 

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Posted 2016-August-10, 21:57

Mike Lawrence in his book on opening leads said opening leads often determine the fate of a contract, but that even the very best players make the wrong opening lead about a third of the time.

So you're definitely right in thinking it's a difficult part of the game to master.
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#30 User is offline   Zelandakh 

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Posted 2016-August-11, 02:57

View Postrmnka447, on 2016-August-10, 21:57, said:

Mike Lawrence in his book on opening leads said opening leads often determine the fate of a contract, but that even the very best players make the wrong opening lead about a third of the time.

So you're definitely right in thinking it's a difficult part of the game to master.

I think you are missing Rainer's point. If I ask you to name the toss of a coin you will be wrong about half of the time. But it is not difficult to make the "best" choice. Having a choice be wrong often and almost always making the best decision are not mutually exclusive.

There is basically something of a disconnect here in communication. On the one side posters are saying that opening leads are difficult because they are often wrong. On the other, opening leads are not difficult because making the best decision based on only the information at the point of decision is relatively easy.

Both of these things are essentially true but the meaning of "difficult" in each case is different. Similarly the meaning of "wrong" in Mike Lawrence's book is questionable. If I give you a hand and auction and simulations show that Lead A is best 2/3 of the time and Lead B best 1/3 of the time. You would probably say that Lead A is clearly the correct lead. But it is still wrong 1/3 of the time. That does not make it "the wrong opening lead" though. Not having read the book, he might really mean that the wrong opening lead is made a third of the time. That would then have a rather different meaning though and is a considerably more difficult statistic to prove.
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#31 User is offline   barmar 

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Posted 2016-August-11, 08:31

View PostZelandakh, on 2016-August-11, 02:57, said:

Both of these things are essentially true but the meaning of "difficult" in each case is different.

I think the point is that one meaning of "difficult" is not really relevant. The goal of the game (put very simply) is to take as many tricks as possible, not to reduce the mental struggle we go through in that process. So who cares how easy it is to make a decision, what we really care about is whether the decision produces a better result.

I suppose there's a third thing: given a particular hand and auction, in many cases experts and/or simulations will mostly agree on what your lead should be. If you lead something else, that's "wrong", even if it turns out to work in that particular case (you got lucky). For instance, I remember once playing with an LOL in the novice game at an NABC, and she routinely cashed her aces -- a very rookie style of not understanding how short-term gains can have long-term consequences. Her decision process was easy (take your obvious tricks before they go away), but she wasn't making use of even the limited information available to her, so they were clearly "wrong".

#32 User is offline   Zelandakh 

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Posted 2016-August-11, 09:41

View Postbarmar, on 2016-August-11, 08:31, said:

I think the point is that one meaning of "difficult" is not really relevant. The goal of the game (put very simply) is to take as many tricks as possible, not to reduce the mental struggle we go through in that process. So who cares how easy it is to make a decision, what we really care about is whether the decision produces a better result.

Produces a better result on the given hand or produces a better result in the long run? Again you are failing to see the difference in viewpoints between the two groups commenting in this thread.
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#33 User is offline   kenberg 

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Posted 2016-August-12, 07:40

View Postsfi, on 2016-August-07, 05:08, said:

Indeed. One of my personal rules is that I never complain about a choice of opening lead if there was a reason behind it. It's one area where partners almost always get a free pass if they get it wrong.


I think this is an excellent rule. The general concept applies broadly.

As to leading from xx: I once read a book. The author presented a hand where a spot was lead against a suit contract and third hand hand, with not quick side entries, had the familiar problem: If the spot is stiff he needs to rise with his A and give partner the ruff. If the spot is from xx then probably the opening leader has a high trump he is hoping to take, after which he will lead the other x and get his ruff. Which is it?

It's not easy. The author mentioned that players are dealt more doubletons than singletons. True enough. Otoh, if partner would Never lead from a doubleton, then it's a singleton. (I am assuming that from the whole hand, the auction, and the size of the spot that it cannot be from xxx).

Myself, with everyone I play with, it could be from x or xx. And this will sometimes give me a guess when I am third hand. That's ok. He tries, I try, sometimes we get it right, sometimes we don't. But if it is from xx and I get it right, that's a success unavailable to those who never lead from xx.

I try to avoid playing with people who, when something goes wrong, begin the discussion with "Any good player would...". Sometimes I will later realize I should have gotten something right. Other times I figure it was a close call that I got wrong. It is worth the effort to think through which is which, but a free lecture from partner based on little more than the fact things went wrong is not helpful.
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