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Split range multi

#1 User is offline   Kungsgeten 

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Posted 2021-February-24, 15:50

Some people who utilize a multi 2D does so in order to play two ranges of weak twos in the majors. Usually the multi is weaker, while 2M is stronger (Glen Ashton has a variant though where 2D shows 12-15 while 2M show 8-11).

What I rarely see, but think make sense, is to split the range: the multi shows one range if holding one of the majors, and another if holding the other. Could this alllow responder to make more informed decisions when deciding if they should try for game, or does it become too wide-ranging if the opponents overcall 3m?

Example 1:

2D = Weak with hearts, or 10-13 with spades.
2H = 10-13
2S = Weak

A downside of the multi is that the opponents can overcall when holding hearts. Here you still get maxmimum preemptive value when holding the weaker spade variant.

Example 2:

2D = Weak major.
2H = 10-13 with hearts, or trash with spades.
2S = Some other usage.

This is an example of the "major flash" where 2H is weak in hearts or spades. What makes this more playable is that the passable option (hearts, showing 10-13 in this case) is stronger than the weak spade variant (maybe showing 0-5). You could use 2S as pass/correct and get more info when opener have 10-13, or bid 2NT if game is possible vs the trash spade hand.
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#2 User is offline   pescetom 

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Posted 2021-February-24, 15:59

View PostKungsgeten, on 2021-February-24, 15:50, said:

Some people who utilize a multi 2D does so in order to play two ranges of weak twos in the majors. Usually the multi is weaker, while 2M is stronger (Glen Ashton has a variant though where 2D shows 12-15 while 2M show 8-11).

What I rarely see, but think make sense, is to split the range: the multi shows one range if holding one of the majors, and another if holding the other. Could this alllow responder to make more informed decisions when deciding if they should try for game, or does it become too wide-ranging if the opponents overcall 3m?

Example 1:

2D = Weak with hearts, or 10-13 with spades.
2H = 10-13
2S = Weak

A downside of the multi is that the opponents can overcall when holding hearts. Here you still get maxmimum preemptive value when holding the weaker spade variant.

Example 2:

2D = Weak major.
2H = 10-13 with hearts, or trash with spades.
2S = Some other usage.

This is an example of the "major flash" where 2H is weak in hearts or spades. What makes this more playable is that the passable option (hearts, showing 10-13 in this case) is stronger than the weak spade variant (maybe showing 0-5). You could use 2S as pass/correct and get more info when opener have 10-13, or bid 2NT if game is possible vs the trash spade hand.


Not sure where or how you want to play this, but unless you change 10-13 to 13+ both examples look like Brown Sticker for WBF.
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#3 User is offline   nullve 

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Posted 2021-February-24, 18:24

View Postpescetom, on 2021-February-24, 15:59, said:

Not sure where or how you want to play this, but unless you change 10-13 to 13+ both examples look like Brown Sticker for WBF.

I interpret the WBF Systems Policy (a largely nonsensical document, unfortunately) as saying that an opening promising 10+ Milton Work points can never be a Brown Sticker.

The policy doesn't apply in Sweden, though.
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#4 User is offline   nullve 

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Posted 2021-February-25, 02:55

WBF Systems Policy said:

The following conventions or treatments are categorised as ‘Brown Sticker’:

a. Any opening bid of two clubs through three spades that:

i. could be made on 9 high card points or less AND

ii. does not promise at least four cards in a known suit.

EXCEPTION: The bid always shows at least four cards in a known suit if it is weak. If the bid does
not show a known four card suit it must show a hand with 13 high card points or more.
(Explanation: Where all the weak meanings show at least four cards in one known suit, and the
strong meanings show a hand with 13 high card points or more, it is not a Brown Sticker
Convention.
)

[...]

So it seems that e.g.

1M = standard, but not 13*-15 if one-suited with 6+ M (=> 1M-1/N; 2M = 10-12 (instead of 10-15, say))
2 = a) 13*-15, 6+ S b) Weak 2
2 = c) 13*-15, 6+ H d) Weak 2

* Milton Work points

is a Brown Sticker-free structure. :D

I've long known that a Major Flash opening promising 10+ Milton Work points is not a Brown Sticker, but I have not been aware of this particular "loophole".
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#5 User is offline   DavidKok 

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Posted 2021-February-25, 04:34

What do you gain compared to the unmodified multi? As you mention responder might be in a tough position if LHO overcalls (anything really, not just 3m), so you need some benefits to outweigh this downside.
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#6 User is offline   nullve 

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Posted 2021-February-25, 05:51

View PostDavidKok, on 2021-February-25, 04:34, said:

What do you gain compared to the unmodified multi? As you mention responder might be in a tough position if LHO overcalls (anything really, not just 3m), so you need some benefits to outweigh this downside.

Consider how often Responder needs to relay with 2N if

2 = Weak Multi
2 = Intermediate Major Flash

compared to if

2 = Split-range Multi: Weak 2 or Intermediate 2
2 = Split-range Major Flash: Intermediate 2 or Weak 2.

The split range effectively allows Responder to relay with 2/2 on invitational-but-not-too-strong hands in response to 2/, respectively.
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#7 User is offline   Kungsgeten 

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Posted 2021-February-25, 07:19

View Postnullve, on 2021-February-25, 05:51, said:

Consider how often Responder needs to relay with 2N if

2 = Weak Multi
2 = Intermediate Major Flash

compared to if

2 = Split-range Multi: Weak 2 or Intermediate 2
2 = Split-range Major Flash: Intermediate 2 or Weak 2.

The split range effectively allows Responder to relay with 2/2 on invitational-but-not-too-strong hands in response to 2/, respectively.


Some other points:

In the case of 2 as intermediate hearts or really weak with spades, it should allow responder to pass with most hands that doesn't want to invite vs intermediate hearts. If opener has the weak spade hand, the opponents have a lot of strength.

In the case of 2 as weak hearts / intermediate spades it could also make sense to not use 2 as pass/correct, but instead as a forcing relay. This saves you a step (compared to 2NT), which might be useful.

Also (like I mentioned previously) I think you might want the 2 opening to be more frequent than the option in the multi. It could also be a way of going with the field:

- You have 11 hcp and 6 spades. If you open this a multi, they can overcall 2. Not so bad though, as the rest of the field also overcalls 2 after a 1 opening.
- You have 7 hcp and 6 spades. If you open this a multi, they can overcall 2. The field will have opened 2 instead, so opening 2 goes against the field.
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#8 User is offline   DavidKok 

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Posted 2021-February-25, 09:58

I'm afraid I don't quite follow. Let's say you hold Kxx, xx, KQxxx QJx (intended to be invitational opposite 10-13 intermediate spades by partner, change the hand a bit if this example doesn't qualify for you). Let's go through the four possible relevant hands partner can have assuming the non-split multi:
  • Partner has weak hearts, they will open 2, you bid 2 and that ends the auction.
  • Partner has weak spades, they will open 2, you bid 2, partner corrects to 2 and that ends the auction (and be sure to thank your passive opponents).
  • Partner has intermediate hearts, they will open 2, which you should pass.
  • Partner has intermediate spades, they will open 2, after which you make some game try (presumably 2NT), and you will end up in 3 or higher.

If you split the multi by strength, I think the following happens:
  • Partner has weak hearts, they will open 2, you bid 2 and that ends the auction.
  • Partner has weak spades, they will open 2, you bid 2 and that ends the auction (it is harder for the opponents to get in now).
  • Partner has intermediate hearts, they will open 2, you bid 2, partner presumably corrects to 3 (or something else) and you might be in trouble.
  • Partner has intermediate spades, they will open 2, you bid 2. I presume partner now bids 2 with a minimum intermediate hand and bypasses it with a maximum?

You win one round (but not level) of bidding opposite weak spades, one level opposite intermediate spades but end up a level higher opposite intermediate hearts? If I flip the hearts and spades held by responder, so that now we have an invitational hand opposite intermediate hearts, I get the same (but flipped colours) results for the non-split multi. The split multi goes:
  • Partner has weak hearts, they will open 2, you bid 2 and that ends the auction.
  • Partner has weak spades, they will open 2, you bid 2 and that ends the auction.
  • Partner has intermediate hearts, they will open 2, you bid 2, they make some descriptive bid.
  • Partner has intermediate spades, they will open 2, you bid 2, partner bids 2 and that ends the auction.

Hypothetically you can make the agreement that over the non-split 2 a response of 2 is an asking bid, in which case the results would be identical? I must be missing something.

At the same time the split structure makes some significant sacrifices. Opponents have more chances to get in, when they do it is more damaging, and responder cannot raise weak 2-bids on the first round.
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#9 User is offline   Kungsgeten 

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Posted 2021-February-26, 03:28

DavidKok said:

I'm afraid I don't quite follow. Let's say you hold Kxx, xx, KQxxx QJx (intended to be invitational opposite 10-13 intermediate spades by partner, change the hand a bit if this example doesn't qualify for you). Let's go through the four possible relevant hands partner can have assuming the non-split multi:
  • Partner has weak hearts, they will open 2, you bid 2 and that ends the auction.
  • Partner has weak spades, they will open 2, you bid 2, partner corrects to 2 and that ends the auction (and be sure to thank your passive opponents).
  • Partner has intermediate hearts, they will open 2, which you should pass.
  • Partner has intermediate spades, they will open 2, after which you make some game try (presumably 2NT), and you will end up in 3 or higher.



I agree. You forgot about the option where you open 2, they overcall 2 on a so-so five card suit and find their 4 game. At the other table(s) they played weak 2 and this didn't happen. Or maybe you bid 2 (pass/correct) and fourth hand had some way of showing hearts.

DavidKok said:

If you split the multi by strength, I think the following happens:
  • Partner has weak hearts, they will open 2, you bid 2 and that ends the auction.
  • Partner has weak spades, they will open 2, you bid 2 and that ends the auction (it is harder for the opponents to get in now).
  • Partner has intermediate hearts, they will open 2, you bid 2, partner presumably corrects to 3 (or something else) and you might be in trouble.
  • Partner has intermediate spades, they will open 2, you bid 2. I presume partner now bids 2 with a minimum intermediate hand and bypasses it with a maximum?



If you play the variant where 2 is a multi (intermediate hearts or weak spades) then you'll pass 2 holding this hand. At least I would.
If partner has intermediate spades (opening 2) then you'll bid 2 which partner will correct to 2. Now you can make an invitational bid. You're worse of though if they overcall (especially 3m).

DavidKok said:

    Flipped hearts and spades by responder:

  • Partner has weak hearts, they will open 2, you bid 2 and that ends the auction.
  • Partner has weak spades, they will open 2, you bid 2 and that ends the auction.
  • Partner has intermediate hearts, they will open 2, you bid 2, they make some descriptive bid.
  • Partner has intermediate spades, they will open 2, you bid 2, partner bids 2 and that ends the auction.



Now it makes sense to bid 2 over a 2 multi, yes. I agree with these auctions.

DavidKok said:

Hypothetically you can make the agreement that over the non-split 2 a response of 2 is an asking bid, in which case the results would be identical? I must be missing something.


If you mean a non-split 2 which shows a weak two bid in either major, then I think 2 is needed as pass/correct. What I meant is that over a split 2 it makes more sense to use 2 as an asking bid, compared to a weak only 2. The reasoning being that its a bit unlikely (and also tells the opponents quite a bit) to say "I want to play 2 if you're intermediate, but if you're weak I want to play at the 3-level". That's basically saying "If you have hearts they have game in spades".

I'm not sure how good of an idea the split multi is. I think it is a bad idea if you don't include any strong variants in your 2 multi, since a big upside of a weak only multi is that it can be frequently passed. A wider ranging multi (split) will probably not be passed quite that frequently.
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#10 User is offline   DavidKok 

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Posted 2021-February-26, 05:00

I deliberately did not include auctions where the opponents overcall, I think it is clear that the split multi is more vulnerable to this than the non-split multi (where, if the opponents interfere, you at least have a good guess which side holds the majority of the points). As I said I was looking for an upside of the split multi in uncontested auctions to counterbalance this downside. I think it is therefore also currently not relevant to compare it with playing regular weak 2's (which I am a fan of).

View PostKungsgeten, on 2021-February-26, 03:28, said:

If you play the variant where 2 is a multi (intermediate hearts or weak spades) then you'll pass 2 holding this hand. At least I would.
Ah, I did not consider this. I think at matchpoints this is potentially a disaster (would you really brave 2 in a potential 2-3 fit if partner is weak, over 3 if partner is intermediate?), and even at IMPs it's risky. It is quite plausible opponents don't have a game if partner has weak spades. I personally would not consider this an improvement.

View PostKungsgeten, on 2021-February-26, 03:28, said:

If you mean a non-split 2 which shows a weak two bid in either major, then I think 2 is needed as pass/correct.
I meant a multi showing weak with one major, and the direct 2M openings as intermediate. You don't need this pass/correct bid, and can opt to win one level of bidding space by using 2 as an asking relay (over 2) instead of 2NT (I personally don't, but if you are so inclined this would streamline the answers compared to the split strength multi).

View PostKungsgeten, on 2021-February-26, 03:28, said:

I'm not sure how good of an idea the split multi is. I think it is a bad idea if you don't include any strong variants in your 2 multi, since a big upside of a weak only multi is that it can be frequently passed. A wider ranging multi (split) will probably not be passed quite that frequently.
So far I don't really see the upside of splitting the multi like this. You win a little bit on some auctions, lose a bit on others, and generally give the opponents more rewarding chances to obstruct your auction. As I said before, I must missing something.
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#11 User is offline   nullve 

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Posted 2021-February-27, 01:41

Responder will respond 2 (P/C) to 2 on the same set of hands whether

a)

2 = Weak 2 or Intermediate 2
2 = Intermediate 2 or Weak 2

or

b)

2 = Weak Multi
2 = Intermediate Major Flash,

but he will obviously respond 2 (also P/C) to 2 on a much larger set of hands (and 2N on much smaller set of hands) in a) than in b).

So if the bidding goes

2-2N

in b), it will likely go either

2-2

or (less frequently?)

2-2N

in a).
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