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.

Tuesday, July 15, 2008

Study of Highly Effective Bidders

Karen Walker in her Bidding Matters (I've wondered if she would have used Bridge Matters if this site hadn't used it first) column of the ACBL bulletin, continued her long running series "The 12 Habits of Highly Effective Bidders" in the July issue - she was still on "7. They strive to be sensible, not brilliant." Here she tackled "some of the failed ideas I've tried over the years".

"The Nothing 2D" she describes seems aligned with the approach of BridgeMatters's 2Dlay (http://www.bridgematters.com/2dlay.pdf). She describes the Nothing 2D as "In a 2/1 system, opener's rebid of 2D over 2C response is an artificial catchall that denies extra length in his major and adequate stoppers for a 2NT rebid". This set of hands would be quite large (any hand with exactly 5 in M unable to bid 2NT), and her further discussion seems to imply that it is either Ds or the awkward hand with exactly 5 in M that has no other good rebid (some 2/1 styles, like Bergen, park this awkward hand in opener 2NT's rebid, others, like Lawrence, put it in opener's 2M rebid, making 2M either 6+ or the awkward 5).
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She says testing of the Nothing 2D has been "costly" on the first three tries. On the first they had "a painful auction" to 3NT by the wrong side. On the second opener couldn't show five-card diamond length.

The actual auctions were not provided, and I was left wondered if the Nothing 2D was implemented with Nothing for follow-ups. The key to 2Dlay was not just to agree to park the hands into 2D, but over 2D to use 2H as an artificial Checkback by opener to find out what responder did have. This Checkback will find when opener has 5Ds (directly if extra, or via 1M-2C;-2D-2H;-2S(Ds)-2NT/3C;-3D if no extras). The Checkback allows opener to right-side 3NT by having opener rebid 2NT over 2D if opener should play it, or use the Checkback if either player or just responder should play it.

In employing multi-meaning conventions and systems, it is necessary to have the appropriate follow-ups to unwind the types - Nothing follow-ups are just guessworks. Proper follow-ups are the brilliant parts of sensible bidding approaches.

On the 3rd problem hand with the Nothing 2D, "use of the 2D rebid elicited a lead-directing double and we scored one fewer trick in 3NT than the field". This is certainly a problem with conventions, and underscores (pun intentional) the difference between IMPs and Pairs. At IMPs you are willing to pay the costs of lost overtricks in return for additional bidding science to the best spot. At Pairs, the cost of slow revealing sequences are often too high.

Karen Walker's column also covered this idea of modified Bergen:

3C: 4-card constructive raise or 3-card limit (3D asks which)
3D: 4-card limit
3M: Preemptive

She implies this idea "failed" since 3C has trouble if the opponents overcall.

That doesn't seem a lot of trouble to me to put this convention into her "failed" category. One wonders if keeping the bids categorized by values would not work better in competition:

3C: Limit raise, either 4-card limit raise or 3-card limit (3D asks which)
3D: 4-card constructive
3M: Preemptive

In the approach my wife Karen A. and I use, all hands with 14/15+ and 3-4 card support start with 2/1 - we find the slow revealing to work well on hands where slam is possible, and the opponents poorly armed in points rarely come into the bidding.

Using this, one can have a structure like:

2NT: Limit raise, either 4-card limit raise or 3-card limit (3C asks which)
3C: Game raise but not much extras, and not a splinter hand type
3D: 4-card constructive
3M: Preemptive

Over these bids opener will often just place the contract.

At Pairs we want to splinter less often with minimum game going values, to further the aim of maximum non-disclosure. Thus we could have:

2NT: Limit raise, either 4-card limit raise or 3-card limit (3C asks which)
3C: Game raise but not much extras. 3D asks for singleton/void.
3D: 4-card constructive
3M: PreemptiveSplinters: Singleton/void with extras.

We will miss the slams where both opener and responder have minimums, but the splinter hits the perfect mesh of hands to produce slam. However at Pairs, the cost of looking for the mesh is 40 or so revealing sequences, and if at least 2 of those cost overtricks it is not worthwhile mesh hunting.

1 Comments:

  • At 10:08 AM, Blogger MickyB said…

    With regard to modified Bergen, I'd prefer

    3C four cards, mixed or limit
    3D three-card limit

    There are hands that want to bid game opposite a 3CLR but not a 4CLR, if you put both into 3C then you can't sort them out below 3H.

     

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