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When your analysis goes very wrong

#1 User is offline   thepossum 

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Posted 2019-January-30, 19:35

Hi all

I can see where I went wrong a few times on this hand. However, while 5H was not an unreasonable contract on the points (6 is makeable on the finesse), there were still a few pit falls with all the losers and the suit breaks. I made one mistake of not drawing trumps because I thought I may need to cross ruff all my losers. Next when doing my cross ruffs I picked the breaks the wrong way and ended up ruffing high unnecessarily in south and ruffing low incorrectly in north. This is one of those annoying hands in a session which can undo all your good work with positive scores and you totally mess up. So while I can see my errors of analysis after the event how should a player better assess their hand and declarer play. My play has been improving greatly but every now and again something like this happens :(

Note I also was not expecting a low lead from Kxx (and played the Ace although I often finesse if I feel safe - when should you finesse vs playing the Ace on a lead?) but that finesse was not everything that brought me unstuck. It was the trump and loser play. It was IMPs general play so not costly except in terms of points and pride :(

regards P


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#2 User is offline   akwoo 

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Posted 2019-January-30, 22:01

I don't understand why you ruffed with the T!H instead of the 5!H - are you really worried that West could have only 2 diamonds? In that case, East would have started with 6 diamonds and presumably would have opened a weak 2. (Also, as you found out at the end, you can't afford to have the 5!H as a loser; if you'd counted to 11 at the time, you would've figured that out.)

Actually, a better play at trick 7 is to cash the Q!C, discarding a spade from hand. That can't get ruffed, because the opening lead of the 2!C shows that West started with either 3 or 4 clubs (or 1, but we know that isn't the case). Now you don't have to worry about being overruffed, because your other low trump can go on a high trump (drawing trump once) and you only have high trumps left for the cross-ruff.

Also, on trick 12, ruffing the spade is a hopeless play; you're guaranteed to go down by doing that. Better is leading a heart to the K - if the remaining hearts split then the Q!C is good.

(I also don't like opening this hand playing 2/1, though I happily open it playing Precision and would strongly consider it playing Acol.)
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#3 User is offline   The_Badger 

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Posted 2019-January-30, 22:07

Ok, you know where you went wrong and best to forget about this board and put it down to tiredness or lack of concentration and move on. However, did you think about the opponents' hands at trick 1? The reason why I ask this is by trick 6 the Q was established for a discard.

The 2 lead is either a singleton, from three small, three to an honour, or four to an honour - I'm assuming GIB doesn't lead it's lowest from five to an honour (please correct me if I'm wrong). West then turns up with the K at trick 5.

It would be a wily defender who would have led 2 from K2 at trick one. I can't imagine GIB having that vivid an imagination, but a very experienced human defender given the bidding might find such a lead.

If the lead is a singleton, then you would have been down immediately assuming the opponents then find their ruff, so taking the finesse of the Q at trick one is probably, sorry definitely, not an option.

It is always worth trying to determine some of the opponents distribution from a lead. Leads are normally standard, and most defenders will stick to their set leads.

You did what most experienced defenders do before embarking on a crossruff namely cashing your side suit winners before drawing trumps. Better luck next time.
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#4 User is offline   Stephen Tu 

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Posted 2019-January-30, 22:37

Not drawing trumps is right, it's not a mistake; it's the right play! You can't afford to draw trumps because your main goal is to set up the spade suit, which may require 2 or 3 ruffs. Where you messed up is later in the play, where you failed to take advantage of the defense helping you out by attempting to cash the CK (always reassess in middle of play in light of unexpected break or developments, possibly modify your initial plan), and not anticipating the danger of a spade overruff. After you get your first spade ruff you should immediately cash CQ and pitch a long spade, this should be pretty safe against robots and most opponents because it's super weird to lead low from Kx doubleton of clubs, and even if the 1 in 500 chance LHO ruffs this it's one fewer spade to ruff and you aren't down yet. You should also note the fall of the SJ on the ruff, which should have woken you up to the danger of a third round overruff (though you should be woke to that even without the honor falling). 5-2 spades is more common than 6-2 diamonds so it's more crucial to ruff third spade high than 3rd diamond high, plus scoring your 2nd low trump in hand prepares for high cross-ruff later.
Finesse or not trick one ... basically when dummy comes down you need to make a plan for how you will get all your tricks. You take the finesse if you think it's part of the best plan, that it's higher percentage than hoping for some other things, if it will gain you a trick if it works. Here, you can see that you can avoid a club loser by pitching on diamonds, so the finesse doesn't really help you in the minor suits. It only helps you if it works AND the diamond pitch helps you in spades, which is only true if the fifth spade is a loser. But at trick one you should be thinking that the fifth spade is likely a winner; after most common 4-3 break if you can ruff spades a couple times the fifth spade is likely to be good, or sometimes you can just give up a 2nd spade to establish the fifth. So eschewing the club finesse is probably right, as you avoid a club loser for sure, and even if it wins, it may not help you at the end(it only helps you on this hand because spades 5-2 offside behind you; if 4-3 or 5-2 the other way the finesse probably doesn't increase your trick count even when it works).

In any case, you should take advantage of BBO making bridge master free, it will improve your play a lot. Also consider reading some books on declarer play, like Root "How to Play a Bridge Hand", Mollo & Gardner "Card Play Technique", to start with.
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#5 User is offline   thepossum 

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Posted 2019-January-30, 23:42

Hi Akwoo and Badger and Stephen

I guess its my Acol side coming out when I open a hand like that. It had a good distribution though and I like to be somewhat preemptive.

As you both say there was a sequence of errors hich I realised as I made them (mostly). I just hadn't done the required analysis of possible distributions

Thanks for the tip on the finesse. At least that was the correct decision :)

But yes, I know about the relative likelihood of 5-3 vs 6-2 break in diamonds. If anything was a bit unlucky (on probability) it was finding a 5-2 spade break but with such good trumps I had plenty of high trumps to spare so no reason to go low

It could be a good count the errors hand :)

P

PS I do use Bridge Master sometimes up to Intermediate (and even the advanced hands). However I often feel I learn more seeing where I went wrong on my bad IMP hands. The situations in Bridge Master are slightly unrealistic and simplified for training use but they are good for teaching principles
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#6 User is offline   Stephen Tu 

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Posted 2019-January-31, 00:33

Although bridgemaster hands and book hands are usually simplified to focus on particular themes, what's good is they consistently punish you for making errors. Random IMP hands, especially if you are looking at only the hands you lost IMPS on, you are probably missing recognizing a crapload of errors you are making, that you happened to get away with because the distribution was friendly. Sometimes bridge is such that the percentage play fails, and the anti-percentage play succeeds. Or one can make nullo plays that are truly never win, can only lose, but you get away with it because lucky on the hand. If you want to really get good, you have to not only look at the bad IMP hands, you have to look at all the hands, and ask yourself if your line was truly optimal on every board, or if it could be improved. Would it still have worked if things broke worse or critical opp's card switched? Or did you just get lucky? And the opposite also holds; with the bad IMP hands, sometimes the conclusion is that you played correctly and just got unlucky. But it takes a lot of study to get good enough to really correctly analyze whether you played a hand right. The double dummy analysis is often different from the single dummy percentage line.

Generally I think most people will benefit far more from playing/studying 100 bridgemaster/quiz book hands than thousands of random regular hands, when they don't have an expert reviewing their play and pointing out the zillion errors they are making that they happened to get away with because the distribution of unknown cards didn't happen to be there to punish them for their mistake. The skills transfer to random hands. Random hands, I find that many opponents are just completely oblivious to the number of errors they are making but happen to get away with, they are making way more errors than just the boards they go down on, and don't notice. As you get better you just get more capable of noticing more & more subtler errors.
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#7 User is offline   thepossum 

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Posted 2019-January-31, 01:20

Hi Stephen

Sure. I agree with everything you say. I do analyse many of the hands, not just the poor ones, but a very bad IMP score is an indication that something went very wrong. I also understand your point about double dummy. It concerns me somewhat that with the increase in power and quality of bridge analysis that we (people) become too obsessed with what could be made in an unrealistic scenario when the single dummy or expert play is what we need to concentrate on. I would always put the guidance of expert bridge players and the accepted guidelines on play ahead of a double dummy analysis.

I would like to think that bridge software will move more towards an expert/double dummy fusion bridge playing approach rather than a simulation analysis based upon double dummy simulation. Then maybe there will be a bridge program that can truly hold itself up as a good player. I know this is the wrong forum but I fear bridge could go down the path of chess and much of AI relying too much on massive computer power than on actual smart play.

best P
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