BridgeMatters

This blog provides supplementary thoughts and ideas to the www.bridgematters.com 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.

Friday, December 18, 2009

Freeing up the one level for two hand types


Success factors/priorities for a system:

- Separation of balanced (bal) and unbalanced (unbal) hand types below 18
- Opening showing 4Ss unbal
- Openings showing 5+Ss or 5+Hs
- Openings showing a minor suit unbal, can be combined with a big hand type

This requires two opening suit bids at the one level to be freed up, one to show 4Ss unbal, and the other the balanced hand outside of the 1NT range.

Here's a mid-chart example:

1C: 4+Ds, 10+, unbal, fewer than 4Ss OR 17+ Cs or 18+ Any
1D: 4Ss, 10-17, unbal, often longer second suit OR 16-17 7+Cs
1H: 15-17 bal
1S: 5+Ss, unbal, 10-17
1NT: 12-14 bal
2C: 6+Cs or 5Cs+4Hs, fewer than 4Ss, unbal, 10-16
2D: 5+Hs, fewer than 4Ss, singleton if just 5Hs, 15-17
2H: 5+Hs, fewer than 4Ss, singleton if just 5Hs, 10-14

Since the ACBL has further restricted mid-chart (senior citizens more comfortable, younger players less fun or less younger players), the 1D opening cannot be a pure 4S bid anymore - here we add the 16-17 7Cs option to make it a "catch-all" that does not promise any particular suit.

1H and 2D are 15-17 artificial, since 15+ artificial openings are allowed, but 14s would not be upgradable into these openings. The shapes 2-5-4-2 and 2-5-2-4 exactly would have to be treated as balanced, as the 2D and 2H openings promise a singleton if just 5Hs. The 1C(two-way)-1D(negative);-P (minimum, Ds unbal) sequence is the way scientists get to the standard 1D all pass.

Here's a super chart:

1C: 4+Ds, 10+, unbal, fewer than 4Ss OR 17+ Cs or 18+ Any
1D: 11-14 bal
1H: 4Ss, 10-17, often longer second suit
1S: 5+Ss, unbal, 10-17
1NT: 14/15-17 bal
2C: 6+Cs or 5Cs+4Hs, fewer than 4Ss, unbal, 10-16
2D: 5+Hs, fewer than 4Ss, singleton if just 5Hs, 14-17
2H: 5+Hs, fewer than 4Ss, singleton if just 5Hs, 10-13

The 2H and 2D openings will hurt sometimes, taking up too much of our bidding space, but the opening makes it easier to get to 4H without the opponents reaching 4S, a common irritating circumstance.

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Saturday, December 05, 2009

MOB Wars


Bridge pro Curtis Cheek, recovering from a life threatening bout with H1N1 just after this summer's world championships, was quoted in this week's San Diego bulletins (Wednesday 2nd):
Cheek was in the hospital for about one month. After they withdrew the drugs that kept him in a coma, it took another week for him to come out of it. He was in a dream-like state and thought he was in Washington DC. He says he would think he was having a normal conversation but was saying things that didn't make sense. "I would wake up and say "The mafia are coming, bid your majors first," he says.
Before I continue I want to wish Cheek, a really great guy, a full recovery as soon as possible.

MAFIA is a term used in some bridge bidding systems, and it means Majors First Always - and his quote does make sense to system designers: "the MAFIA systems are coming: bid your majors first".

Blending a majors oriented approach with a focus on balanced hand types as discussed in the last post, I produced a new plug-n-play system, MOB Club:

http://www.bridgematters.com/mobclub.pdf

1C: 10-16 with a four card major, unbalanced, or 17+ (not a five card major vulnerable unless near GF)
1D: balanced or 14-16 with Ds, unbalanced and no four card major
1H/S: five card major, unbalanced, limited to 16 not vulnerable
1NT: variable
2C: 10-16, no four card major, 6+Cs or 5Cs 11-13 with 4Ds
2D: 10-13, no four card major, 6+Ds or 5Ds 11-13 with 4Cs

MOB is Major or Big, and the one club opening shows either 10-16 unbalanced with a four card major (exactly), or various 17+ hand types. The fundamental concept is that with a five card major unbalanced you open it, and with a four card major unbalanced, open 1C, and then bid the major (usually over 1D). Not vulnerable the major suit openings are limited to 10-16, to allow bounces to game even with considerable strength, much like with a big club system. The major openings structure has Sazzilli, Simplified Gazzilli, which takes advantage that the major opening is never a 5-3-3-2 balanced hand type.

Majors hands that are 5-3-3-2 are always treated as a balanced hand type first - one could call this BOM - Balanced Over Majors - approach. Thus when one diamond is opened and is balanced, it can have a five card major, unlikely the 1D nebulous opening in big club systems like Meckwell Lite.

The MOB one diamond opening is mostly balanced - a balanced hand less than 17 not in the 1NT opening range. The system uses a variable notrump (since 10 to 13s are nasty weapons not vulnerable), and thus the balanced range for 1D changes.

However the 1D opening is not purely balanced, as discussed in the last post. Instead it is combined with diamonds, extras, unbalanced, and no four card or longer major. The purpose of adding this hand type in is first to use the many suit rebids possible for opener - if the opening is just balanced opener will just rebid notrump or support responder's suit. In addition in competition the balanced hand type can keep quiet, while the unbalanced hand with extras can compete to show shape and values. Moving the unbalanced hand type into 1D allows the 2D opening to be limited, in a Fantunes style, but here the 2D denies a four card major, which allows responder to quickly place the contract, first choice being to pass on many hands.

MOB achieves high definition openings for 1D and higher by having a nebulous, or messy, 1C opening. Moving the nebulous opening to the lowest opening possible gives plenty of room to unwind the hand types, while restricting the 10-16 hands in the 1C opening to a specific set of hands keeps the bidding manageable if it gets competitive. Certainly the opponents can jam the 1C opening by bidding aggressively over it, but they risk missing their own fits, and games and slams, if they don't bid constructively, since the 1C opening doesn't promise strength like in a big club system. If the opponents do bid constructively over the 1C opening, their bidding will often assist opener and responder in determining their own fit and values.

It would be easy to modify MOB to bring it closer to SOB (Spades or Big).

1C: 10-16 with 4Ss, unbalanced, or 17+
1D: balanced or 14-16 with Ds, unbalanced and no four card major
1H: 4+Hs unbalanced, not 4-4 majors, limited to 16, often just 4Hs if 10-13
1S: 5+Ss, unbalanced, limited to 16
1NT: variable
2C: 10-16, no four card major, 6+Cs or 5Cs 11-13 with 4Ds
2D: 10-13, no four card major, 6+Ds or 5Ds 11-13 with 4Cs
2H: 10-13, 5+Hs, fewer than 4Ss

Here the one heart opening loses a bit of definition (can just be 4Hs now), but that makes the 1C opening precise in the 10-16 range. No system is perfect - as a designer one is always going to have to park some hand types into an opening that one would prefer not to - such are the compromises that produce the variety of bidding systems.

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