BBO Discussion Forums: K-S question - BBO Discussion Forums

Jump to content

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

K-S question

#1 User is offline   Flem72 

  • PipPipPipPipPip
  • Group: Full Members
  • Posts: 506
  • Joined: 2011-March-04

Posted 2017-September-29, 16:18

it's been a while since I played WNT with someone who did not follow K-S in auctions like 1M-1M/2M, but there are folks around here who want that 2M to be 12-15, 3-card support OK. Long and short, how does K-S handle something like x=AKxx=Qxxxx=AJx or x=AKxx=AQx=Jxxxx after 1m-1S? How about Kxx=AKxx=x=Kxxxx in the same auction? I know some old-time K-S players who will open 1H on these, 1S always claiming five cards, but....
0

#2 User is offline   hrothgar 

  • PipPipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 15,495
  • Joined: 2003-February-13
  • Gender:Male
  • Location:Natick, MA
  • Interests:Travel
    Cooking
    Brewing
    Hiking

Posted 2017-September-29, 16:49

View PostFlem72, on 2017-September-29, 16:18, said:

it's been a while since I played WNT with someone who did not follow K-S in auctions like 1M-1M/2M, but there are folks around here who want that 2M to be 12-15, 3-card support OK. Long and short, how does K-S handle something like x=AKxx=Qxxxx=AJx or x=AKxx=AQx=Jxxxx after 1m-1S? How about Kxx=AKxx=x=Kxxxx in the same auction? I know some old-time K-S players who will open 1H on these, 1S always claiming five cards, but....



As I recall, with

Hand 1: Open 1, rebid 2

Hand 2: Open 1, rebid 1N

Hand 3: Open1, rebid 1NT
Alderaan delenda est
0

#3 User is offline   straube 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,082
  • Joined: 2009-January-18
  • Gender:Male
  • Location:Vancouver WA USA

Posted 2017-September-29, 23:14

From Kaplan-Sheinwold Updated by Edgar Kaplan...

1m-1M, 1N "opener has 15 to 17 balanced, with no 4-card major (but after 1m-1S he may have 4 hearts)..."

1m-1M, 2M "Usually 15-17, 4-card fit. Could be unbalanced equivalent. Rarely, 3-card support, too concentrated for 1N rebid: AQx xx xxx AKQxx"


1D-1M, 2C "Forcing. Strong rebid, like a reverse, but does not promise long diamonds absolutely; guarantee a rebid...."

1m-1M, 2m "Severely limited; 12 to 14 and not 14 if good 6-card suit. Could be 5-card suit; if 6-cards, a terrible suit or a terrible hand..."

From this I would have to conclude that each of these hands open and rebid their minor.
0

#4 User is offline   rmnka447 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,366
  • Joined: 2012-March-18
  • Gender:Male
  • Location:Illinois
  • Interests:Bridge, Golf, Soccer

Posted 2017-September-29, 23:50

K-S minor suit auctions were developed to take into account the different nature of the population of the hands that you open 1 of a minor. Playing strong NTs, 1 0f a minor openers are only more than a minimum opening hand about 25% of the time. Playing weak NTs, 1 of a minor openers are more than minimum opening hands a little more than 65% of the time. So many of the bidding sequences were changed to reflect the greater strength of hands. In particular, the major suit raise ranges were changed, so after:

1 m - 1 M
?

2 M reflects 15-17 HCP and 4 trumps
3 M reflects 18-19- HCP and 4 trump, and,
4 M reflects 19+-20 HCP and 4 trump.

What do you do when you have a 12-14 and 4 trump? Normally, you raise to 2 M anyhow. Responder should always act based on the expected 15-17/4 trump hand and alert that understanding for the opponents. This occasionally may get you too high, but remember that if you have a 12-14 minimum opener it has to be unbalanced. So the distribution may make up some for what is lacked in HCP. In practice, these type of raises don't come up all that often. From my experience, I guess maybe once every 3-4 sessions. And it only may become a potential problem if partner has enough to make a further invite or game bid opposite the supposed 15-17 raise. OTOH, this disadvantage will be offset by the times you end up in a 4-4 major fit with a hand where responder would have passed a strong NT opener. Also, the invitation structure by responder remains consistent with how the strong NTers are inviting in a Stayman or Transfer auction.

If you maintain the "standard" major raises after a minor opening (2 M 13-15, 3 M 16-18), there are some issues. First, with the 15-17 balanced hands that used to be opened with a strong 1 NT, opener must raise to 2 M with the 15 hand, but raise to 3 M with the 16-17 hands. Responder also has to decide when to raise to game opposite the 16-18 raise as there is no way to invite. And the jump raise to 3 M is going to happen more often because of the differences in the pool of hands opened 1 of a minor.

Edgar Kaplan updated K-S in the late '60s and many K-S adherents adopted some of these changes. One of the most widely adopted changes was the interchange of the meanings of minor rebids in after opening 1 . So that

1 - 1 M
2

shows at least reversing values, and,

1 - 1 M
3

shows a weak minor hand presumably something like 5-5 in the minors. This change clarified that the 2 rebid was always strong. In the original K-S, a 2 rebid could either be a strong balanced/unbalanced hand up to about a hand value equivalent of a jump 2 NT rebid or a weak 5-5 hand. Practically, this sometimes caused a problem for responder because of the ambiguity of the bid

If you have a minimum unbalanced minor hand, the only way to show it is to rebid 2 of the original minor unless you have a hand you can show as a weak minor 2 suiter (by one of the above methods).
0

#5 User is offline   rmnka447 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,366
  • Joined: 2012-March-18
  • Gender:Male
  • Location:Illinois
  • Interests:Bridge, Golf, Soccer

Posted 2017-September-30, 00:48

View Poststraube, on 2017-September-29, 23:14, said:

From Kaplan-Sheinwold Updated by Edgar Kaplan...

1m-1M, 1N "opener has 15 to 17 balanced, with no 4-card major (but after 1m-1S he may have 4 hearts)..."

1m-1M, 2M "Usually 15-17, 4-card fit. Could be unbalanced equivalent. Rarely, 3-card support, too concentrated for 1N rebid: AQx xx xxx AKQxx"


1D-1M, 2C "Forcing. Strong rebid, like a reverse, but does not promise long diamonds absolutely; guarantee a rebid...."

1m-1M, 2m "Severely limited; 12 to 14 and not 14 if good 6-card suit. Could be 5-card suit; if 6-cards, a terrible suit or a terrible hand..."

From this I would have to conclude that each of these hands open and rebid their minor.

In the original K-S system and the update, opener could in practice have a balanced 15-17 hand on the following auctions:

1 m - 1
1

or

1 - 1
1 M.

So a major rebid by opener presumably promised 15+.

But some practical problems with this approach was that the length of opener's minor was not certain, these auctions frequently led to wrong siding NT when opener was balanced, and with a minimum minor opener with a 4 card major opener always had to rebid 2 of a minor.

The answer to the first two above problems was simple -- simply rebid 1 NT with the balanced 15-17 hand and use some sort of checkback bid over 1 NT. That bid turned out to be what is now called NMF. As a result, any 1 m opener followed by a 1 M rebid by opener shows an unbalanced minor opener with equal or longer m length (could be 4441).

The last problem still exists anytime opener has a minimum minor opener. It will always exist where opener has a minimum minor opener with a 4 card suit and responder's initial response is 1 . However, the above auctions could be used on ANY value opener if responder has an opening values asking bid available. We use 2 as the ask with opener's 2 rebid showing the minimum opener and any other rebid showing the good (15+) hand. Most often this comes up when responder has a fit for opener's major.
0

#6 User is offline   straube 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,082
  • Joined: 2009-January-18
  • Gender:Male
  • Location:Vancouver WA USA

Posted 2017-September-30, 12:43

How about x Axxx AJxx Kxxx ? Open 1N? They can't open 1D and "reverse" into clubs.
0

#7 User is offline   hrothgar 

  • PipPipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 15,495
  • Joined: 2003-February-13
  • Gender:Male
  • Location:Natick, MA
  • Interests:Travel
    Cooking
    Brewing
    Hiking

Posted 2017-September-30, 13:46

View Poststraube, on 2017-September-30, 12:43, said:

How about x Axxx AJxx Kxxx ? Open 1N? They can't open 1D and "reverse" into clubs.


Open 1N or pass (There are examples close to this one in my KS book where you pass)
Alderaan delenda est
0

#8 User is offline   Stephen Tu 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,100
  • Joined: 2003-May-14

Posted 2017-September-30, 15:25

1444 KSU suggests 1H and rebid 1nt over 1s (since that particular sequence shows 12-14 unlike opening in a minor), pass if 1h-1nt. Or pass the marginal ones.
0

#9 User is offline   rmnka447 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,366
  • Joined: 2012-March-18
  • Gender:Male
  • Location:Illinois
  • Interests:Bridge, Golf, Soccer

Posted 2017-September-30, 15:31

View Poststraube, on 2017-September-30, 12:43, said:

How about x Axxx AJxx Kxxx ? Open 1N? They can't open 1D and "reverse" into clubs.

This is a system problem hand for K-S. It's enough so that one of our K-S team partnerships play Mini-Roman instead of Flannery.

If you don't play anything special to handle this type of hand, you basically stuck opening and rebidding your minor. Fortunately, the times that you hold a stiff and partner specifically replies 1 is relatively rare.
0

#10 User is offline   straube 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,082
  • Joined: 2009-January-18
  • Gender:Male
  • Location:Vancouver WA USA

Posted 2017-September-30, 16:24

View Postrmnka447, on 2017-September-30, 15:31, said:

This is a system problem hand for K-S. It's enough so that one of our K-S team partnerships play Mini-Roman instead of Flannery.

If you don't play anything special to handle this type of hand, you basically stuck opening and rebidding your minor. Fortunately, the times that you hold a stiff and partner specifically replies 1 is relatively rare.


I would think a 1S response would be frequent whenever holding 1-4-4-4. In ACBL-land I know you can't systemically open 1N with a singleton (not to say you can't open 1N on occasion with one).
0

#11 User is offline   rmnka447 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,366
  • Joined: 2012-March-18
  • Gender:Male
  • Location:Illinois
  • Interests:Bridge, Golf, Soccer

Posted 2017-October-03, 21:05

View Poststraube, on 2017-September-30, 16:24, said:

I would think a 1S response would be frequent whenever holding 1-4-4-4. In ACBL-land I know you can't systemically open 1N with a singleton (not to say you can't open 1N on occasion with one).

1 is likely to be more frequent, but there are also responding hands that require other responses over a minor opening on this hand. So, in essence, we're talking about an opening hand that doesn't come up that often and a problem response that comes up only part of the time that you make that opening with this hand. So you have to decide what's the best way to bid that's likely to cause the least problems.
0

#12 User is offline   Flem72 

  • PipPipPipPipPip
  • Group: Full Members
  • Posts: 506
  • Joined: 2011-March-04

Posted 2017-October-04, 07:35

View Postrmnka447, on 2017-October-03, 21:05, said:

1 is likely to be more frequent, but there are also responding hands that require other responses over a minor opening on this hand. So, in essence, we're talking about an opening hand that doesn't come up that often and a problem response that comes up only part of the time that you make that opening with this hand. So you have to decide what's the best way to bid that's likely to cause the least problems.


Playing with an infrequent partner in a 28 board Swiss, we had this problem hand 4 times. Maybe I won't see it again for a couple years.....
0

#13 User is offline   Flem72 

  • PipPipPipPipPip
  • Group: Full Members
  • Posts: 506
  • Joined: 2011-March-04

Posted 2017-October-04, 07:39

View Postrmnka447, on 2017-October-03, 21:05, said:

1 is likely to be more frequent, but there are also responding hands that require other responses over a minor opening on this hand. So, in essence, we're talking about an opening hand that doesn't come up that often and a problem response that comes up only part of the time that you make that opening with this hand. So you have to decide what's the best way to bid that's likely to cause the least problems.


Playing with an infrequent partner in a 28 board Swiss, we had this problem hand 4 times. Maybe I won't see it again for a couple years in a WNT context.
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