The origin of this modification of this conventional defense method is unknown. The features behind the concept of this variation are employed after a No Trump opening by an opponent. Whether or not the concept can / should be employed in the immediate seat and/or as a balancing action is dependent on the partnership agreement.
The reader should also compare this modified version to the original Wallis conventional defense method devised by Mr. Peter James Wallis of Brisbane, Australia. One of the main features, which differs from the original version is the employment of the double, used for penalty.
The following outlines the meanings of these overcalls:
Double: Any double is for penalty. Partner must pass.
Shows an unspecified Major suit (either Hearts and Spades) and an unspecified Minor suit (either Clubs and Diamonds).
Show both Major suits.
A natural bid and shows a long, independent Heart suit of 5/6 plus in length.
A natural bid and shows a long, independent Spade suit of 5/6 plus in length.
Note: This Modified Wallis variation is somewhat dependent on the bidding system employed and can be altered or varied to meet the requirements of the particular bidding system.
Note: Some partnerships have agreed that the distribution of the holding, when overcalling could / may be reduced to 4-4 in both Major suits regardless of the state of vulnerability, otherwise the distribution is generally 5-4, 4-5, or 5-5 depending on the state of vulnerability. This is entirely a partnership agreement in all employed variations of the concept.
Note: Most partnership agreements understand that all bids of 2 No Trump and higher are natural or preemptive.
Since there are many idle bids available, the partnership can untilize them for other shapes, patterns, and distributions. Any jump response by the Advancer can / may constitute strength and length, but this again is an individual partnership understanding.
If you wish to include this feature, or any other feature, of the game of bridge in your partnership agreement, then please make certain that the concept is understood by both partners. Be aware whether or not the feature is alertable or not and whether an announcement should or must be made. Check with the governing body and/or the bridge district and/or the bridge unit prior to the game to establish the guidelines applied. Please include the particular feature on your convention card in order that your opponents are also aware of this feature during the bidding process, since this information must be made known to them according to the Laws of Duplicate Contract Bridge. We do not always include the procedure regarding Alerts and/or Announcements, since these regulations are changed and revised during time by the governing body. It is our intention only to present the information as concisely and as accurately as possible.
Claus and Raymond Conventions Bridge Sites Home Page I Glossary Home Page II NT Defense Methods