BBO Discussion Forums: Comparing two lines - BBO Discussion Forums

Jump to content

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

Comparing two lines

#1 User is offline   antonylee 

  • PipPipPipPip
  • Group: Full Members
  • Posts: 499
  • Joined: 2011-January-19
  • Gender:Male

Posted 2020-March-28, 13:08


Teams.
On the J lead you can either go for the simple heart finesse (with a fallback on AK onside available), or try AKJ pitching diamonds -- possibly cashing the A first.
While it may be possible to list all winning cases for the second line, the enumeration gets quickly unwieldy -- especially if you have to do it at the table! Any suggestions on how to practically evaluate the winning chances of that approach?
0

#2 User is online   smerriman 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,777
  • Joined: 2014-March-15
  • Gender:Male

Posted 2020-March-28, 14:47

View Postantonylee, on 2020-March-28, 13:08, said:

.. or try AKJ pitching diamonds -- possibly cashing the A first.

I'm probably missing something obvious here, but how is this a line? If you lose a trick to the Q, you still have 2 diamond losers, so need the trump K onside. If East covers with the Q and you ruff - or it drops in the first two rounds - you still haven't achieved anything in diamonds and need the trump K onside.
0

#3 User is offline   Cyberyeti 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,934
  • Joined: 2009-July-13
  • Location:England

Posted 2020-March-28, 15:33

View Postsmerriman, on 2020-March-28, 14:47, said:

I'm probably missing something obvious here, but how is this a line? If you lose a trick to the Q, you still have 2 diamond losers, so need the trump K onside. If East covers with the Q and you ruff - or it drops in the first two rounds - you still haven't achieved anything in diamonds and need the trump K onside.


You are missing a lot, if the Q drops double you're in great shape, if it's covered on the third round you're also good, ruff high, cross to A and lead 10, if the short hand had Kx, he can do nothing to you, if xx onside with 3 spades, you overruff, cross back with the club and lead the 5th spade discarding the diamond, there are lots of chances, but still not sure how good.
0

#4 User is online   smerriman 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,777
  • Joined: 2014-March-15
  • Gender:Male

Posted 2020-March-28, 15:43

Ah, I see now, thanks.
0

#5 User is offline   nige1 

  • 5-level belongs to me
  • PipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 9,128
  • Joined: 2004-August-30
  • Gender:Male
  • Location:Glasgow Scotland
  • Interests:Poems Computers

Posted 2020-March-28, 18:34

AntonyLee writes 'Teams.
On the J lead you can either go for the simple heart finesse (with a fallback on AK onside available), or try AKJ pitching diamonds -- possibly cashing the A first. While it may be possible to list all winning cases for the second line, the enumeration gets quickly unwieldy -- especially if you have to do it at the table! Any suggestions on how to practically evaluate the winning chances of that approach?'
+++++++++++++++++++++++++++++++++++


If the decision is close and difficult, it is probably best to toss a coin, rather than mentally exhaust ourselves.

No shortcut but initially, perhaps ...
- Look for the best line without bothering by how much it is best.
- Attempt drastic simplifying assumptions.
- Ensure they are relatively/qualitatively reasonable
- Rather than absolutely/quantitatively accurate.
- Watch out for extreme anomalies.

For example, focus on normal breaks. Here you might assume
- break 2-2 or 3-1.
- break 3-3 or 4-2.
- break 4-3 or 5-2.

Guesses:
Line 1 ( finesse: About 60% (LHO has K -- about 50%. Failing that RHO has AK or AKx -- < 25%)

Line 2: A then s: About 55%: K is singleton (10%). Failing that RHO has Q (50%).

Line 3: s then s: More than 60%
(a) if RHO has Q then A and another .
(b) If LHO has Q, then finesse.
(Usually succeeds when RHO has Q -- about 50%). Failing that when LHO started with K and can't obtain a or ruff -- more than 30%.

We should take the silence of opponents into account and also their defensive skills but, on the whole, I reckon that line 3 is best. Caveat: Arithmetic is not my long suit and I welcome correction.

0

#6 User is offline   Cyberyeti 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,934
  • Joined: 2009-July-13
  • Location:England

Posted 2020-March-29, 03:34

The chance of E having AK is of course raised by the fact that if W had AK, he'd surely have led one. ALso I know you were ignoring 5-1 breaks in diamonds, but if they are 5-1 the lead implications would suggest the stiff is a top honour.
1

#7 User is offline   TomSawyer4 

  • PipPip
  • Group: Members
  • Posts: 12
  • Joined: 2019-August-19

Posted 2020-March-29, 10:48

Its beyond my abilities to solve that, and
Intuitively I would take the AKJ of spades from that choice,

but:

How about a third line:

Win the King of Clubs and cross to the Ace of Clubs, lead the four of diamonds and play the deuce underneath it, forcing the defense to be perfect to claim three diamond tricks. At worst, defence takes three diamond tricks and the heart king must be onside to make the hand

This has the advantage of making whenever East is forced to take a diamond (even by roughing) and has no diamond to return. I.e. Club is rough/slough, Heart is the needed finesse, spade is a free finesse and the AKJ, heart finesse choice all over again but with more knowledge and no worries about the Q of spades.
0

#8 User is offline   bascule 

  • Pip
  • Group: Members
  • Posts: 3
  • Joined: 2011-July-05

Posted 2020-March-30, 07:06

Which odds do you want, take the 50% trump finesse or aim for miracles. Be sick, if the field is taking the winning finesse, and one does not and fails.
0

#9 User is offline   msjennifer 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,366
  • Joined: 2013-August-03
  • Gender:Female
  • Location:Variable private
  • Interests:Cricket,Photography,Paediatrics and Community Medicine.

Posted 2020-March-30, 11:00

Sirs,
With so many lines available there remains one VERY RARE combination to be considered. Eliminate clubs after cashing one top spade ,wish that the trumps, mandatorily,are 2-2 ,(finesse is immaterial) ,and diamonds are blocked with either having DAJ OR KJ stiff or RHO with AKx .One can win by cashing HA and endplay either opponent who holds the HK. A possibility of dropping a singleton trump king may increase the percentages slightly. I, do remain confused with so many options available but shall normally take the 50 p.c. trump finesse ( having no clues).THANKS.
0

#10 User is offline   Vampyr 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,611
  • Joined: 2009-September-15
  • Gender:Female
  • Location:London

Posted 2020-March-30, 14:38

View PostTomSawyer4, on 2020-March-29, 10:48, said:

Its beyond my abilities to solve that, and
Intuitively I would take the AKJ of spades from that choice,

but:

How about a third line:

Win the King of Clubs and cross to the Ace of Clubs, lead the four of diamonds and play the deuce underneath it, forcing the defense to be perfect to claim three diamond tricks. At worst, defence takes three diamond tricks and the heart king must be onside to make the hand

This has the advantage of making whenever East is forced to take a diamond (even by roughing) and has no diamond to return. I.e. Club is rough/slough, Heart is the needed finesse, spade is a free finesse and the AKJ, heart finesse choice all over again but with more knowledge and no worries about the Q of spades.


Since the heart finesse is enough for the contract, why let the defenders take three diamonds or two diamonds and a rough ruff first? (If they cannot manage this, I would call an undertaker). If you are relying on the finesse you might as well take it immediately.
I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones -- Albert Einstein
0

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

1 User(s) are reading this topic
0 members, 1 guests, 0 anonymous users