This blog provides supplementary thoughts and ideas to the site. If you haven't seen the main site, there is a lot there including the Martel and Rodwell interviews, photos, and articles. This blog is focused on advancing bridge theory by discussing the application of new ideas. All original content is copyright 2009 Glen Ashton.

Wednesday, April 25, 2007

Let's go for another design walk to look at the considerations for system designers. Most systems start with a base premise, and here it will be that balanced hands show themselves quickly, with a bid that means only balanced. This seems like a good core concept, but how to deliver it?

So 1NT could be 12-14, and if 18+ balanced we will open on two level, say Mexican 2D for 18-19, 2NT for 20-21, 2C for 22+, so 2C will be like standard, also handling big unbalanced hands.

So where do we park 15-17 balanced? This type of concern is always key for system designers - where to place a set of hands so it has sufficient bidding space available for it, yet it conserves bidding options as much as possible for the rest of the system. We could open it 1S, but now responder plays 1NT if wants to signoff. 1C and 1D could work, but that loses a nice low opening bid. 1H could be just right - responder can pass to sign off in Hs - cool! Responder can bid 1S to relay to 1NT, to play there, or follow-up by showing hand type. Responder can bid 1NT to show 4Ss but signoff value - this might get the contract played by the wrong side, but finds the 4-4 S fit if it is there. The rest of a 1NT structure can be played directly over 1H.

So we have, at the one level:
1H: 15-17 balanced
1NT: 12-14 balanced
1C, 1D, 1S: available, must handle all four suits with less than 2C opening strength and unbalanced.

So we wonder, is this the time for the little major approach, such as:
1C: 4+Hs
1D: 4+Ss
1S: Unbalanced with no 4 card major

What are the awkward and frequent hands now parked in 1S? This is a design question one always needs to ask: are there frequent hands stuck in an opening that will make it hard to find the best spot. Here these frequent and awkward hands would be the 5-4-3-1, having 5-4/4-5 in the minors, and a 3 card major. These need to explore for a 5-3 major fit, but they no longer have the bidding space if they open 1S. And these will come up a lot. So opening these 1S will not work, and thus we need to open unbalanced with a minor by opening either 1C or 1D (or both) to allow for major suit fit investigation. This leaves the 1S opening available, and it might as well show 5Ss: a standard type opening, which we know works. So we have, at the one level:

1H: 15-17 balanced
1NT: 12-14 balanced
1S: 5+Ss, less than 2C opening strength.
1C, 1D: available, must handle unbalanced with Cs, Ds, or Hs

So one of 1C or 1D will do double duty here, handling more than one primary suit. How should we split things up here?

We could do a strength split:
1C: 15+ unbalanced, with Ds, Hs, Cs (and perhaps even Ss, so the 1S opening is limited)
1D: 10-14, unbalanced, not 5+Ss.

Over 1D we seem to have a rebid problem: if it goes 1D-1S--?, opener has to rebid 2H to show Hs, which may be too high without a fit. What about if we flip-flop the major suit responses, so we have:
1D-1H = Ss
1D-1S = Hs

Now after 1D-1H (showing Ss), without a S fit opener bids: 1S=5+Hs, 1NT=Cs, 2C=Ds, 2D=both minors. Or perhaps after 1D-1H (showing Ss), without a S fit opener bids: 1S(a minor, 1NT asks), 1NT (both minors), 2x=natural with Hs. That works.

What if the opponents compete over the 1D bid? They will often do this in Ss. So 1D(10-14)-2S(overcall)-Pass-Pass--? Now opener does not have any strength to come in here on most hands, even though shapely. How about we use an intermediate and weak/strong split:
1C: Unbalanced, not 5+Ss, 10-12 or 17+
1D: 13-16, unbalanced, not 5+Ss.

Now after 1D(13-16)-2S(overcall)-Pass-Pass--?, opener has the strength to compete on a bunch of hands, and also responder can make a value showing double, to get opener to describe hand, after 1D(13-16)-2S(overcall)-?

After the 1C opening (10-12 or 17+), responder assumes 10-12, and opener, if 17+ will show strength later.

At this point, we could now look at a whole bunch of world championship hands and try to guess how this scheme might have worked on each one. Say we do that, and we find that not showing the Hs immediately is costing on a bunch of hands. So we have auctions in the world championships where it goes 1H-4H, but using our new system we open 1D or 1C, responder bids low to find out what opener has, and the opponents come in with Ss. So we reconsider our approach and decide that one of 1C or 1D should show Hs, and the other either minor. We have another question too - should the opening that shows Hs promise 5+Hs or just 4Hs. The advantage of showing just 4Hs, is now we can take these hand types out of the other opening. The disadvantage is that responder does not know about the 5th H. However if responder bids a heart raise to 2H on just 3, and ends up in a 4-3, this is not necessarily bad - we have seen the four card major opening crew (such as the Australians who play transfer major suit openings) use 2 of a major raises with good success - it prevents the opponents from balancing as much since an 8 card fit is not promised, and so the assumed fit (they can assume a fit if we have a fit) is not as pronounced.

Also in looking at it closer, we like some of the collateral fallout if the either minor opening denies 4+Hs. Now if the opponents compete, responder can double to show general values, knowing that opener may rebid in Ss, but not naturally in Hs. In addition, the cheapest H bid by opener can be artificial, showing extras, which will keep the bidding low, and give responder a chance to rebid S if holding 4 of them. So this method seems okay from a competitive standpoint, though we would need to look at a whole bunch of hands to confirm this.

Let's look at our two prime options now:
1C: 4Hs, unbalanced, can have longer minor, less than 2C strength
1D: Either minor, unbalanced, not 4Hs, less than 2C strength.

1C: Either minor, unbalanced, not 4Hs, less than 2C strength.
1D: 4Hs, unbalanced, can have longer minor, less than 2C strength

What's the better scheme? Since the either minor hand type covers more hands, perhaps it should be in 1C, to give it more room to unwind. What we would do now is consider response structures for the two approaches, and we would focus on the either minor opening first, as it promises to get messy. For discussion purposes we will just concentrate on the responses for finding a major suit fit.

After 1D: Either minor, unbalanced, not 4Hs, less than 2C strength.
-- 1H: Relay, now opener's 1S=4Ss
-- 1S: 5+Ss.
-- 1NT: 5+Hs
That seems workable.

After 1C: Either minor, unbalanced, not 4Hs, less than 2C strength.
-- 1D: Relay, now opener's 1S=4Ss, 1H by opener is extra values.
-- 1H: 5+Hs
-- 1S: 5+Ss.

This last one is like a Montreal Relay (the 1D bid denying a 5 card major) combined with a Kokish Relay (the 1H rebid by opener) - since both are invented by Kokish, this would be Double-Barrelled Kokish. With a chance to play Double-Barrelled Kokish, we might just stop the design work right here, under the general principles that we must have arrived at the utopia of bidding design. However a system designer looks for areas where a system can follow a somewhat symmetric approach, so the memory work of the users will be reduced. Here the designer might go with a one-under scheme:

--1H: 4Ss (so one-under the major like the 1D opening bid)
--1S: Cs (following the general one-under idea)
--1NT: Both minors & extras (extras so opener has values if ends up in NT contract)
--2C: Ds
--2D: Both minors, no extras.

So what was the better scheme, opening 1C or 1D with the 4+H hand type? Now the system designer might return to world championship hands, trying to see what are the important characteristics of each scheme. Another consideration for the designer is what is allowed to be played in their country or region. Say the designer was in North America. Now opening 1H as 15-17 balanced would be ACBL Mid-Chart, but a defense would need to get approved as well. The designer might submit one for approval, and while we know defenses don't seem to be getting approved at the moment, the designer might still hope that it does. The sequence 1D(either minor)-1H(relay) would not be Mid-Chart, but the sequence 1C(either minor)-1D(relay, forcing) would be General Convention Chart (GCC), so the designer might go with the scheme that is covered under the GCC.

So the system design might look like:
1C: Either minor, unbalanced, 10/11 to near GF values, fewer than 4Hs, not-forcing
--1D: relay, opener rebids one-under Or bids 1NT or 2D with both minors, 1NT showing extras
--1H, 1S: five or longer in major

1D: 4 or longer Hs, unbalanced, can have longer minor, 10/11 to near GF values

1H: 15-17 balanced

1S: 5 or longer Ss, 10/11 to near GF values

1NT: 12-14 balanced

2C: Strong, 22+ balanced or any GF

2D: 18-19 balanced

2NT: 20-21 balanced

Now as the system is put into play, some might try 1NT as 15-17 and 1H as 12-14. Others might incorporate the 18-19 balanced into 2C. Some might try increasing the range of 1H, making it 15-18, or making it with two ranges, such as 15-17 with 10-11, or 15-17 with 20-21, or 12-14 with 18-20. The system designer can expect that if other partnerships use the system, they will make some modifications to it: putting their own stamp on it and, thus, creating their own unique system.


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