Conventional intervention over 1NT openings Larry Hammick larry@hammick.com 2000.06.06 Contents ;Introduction ;Astro ;;Pinpoint Astro ;;Aspro ;Brozel ;Cansino ;Cappelletti (Capp, Hamilton) ;D.O.N.T. ;Landy and Ripstra ;Suction ;Introduction This article gathers up the more popular conventions by which pairs can get into the bidding after a 1NT opening by the opponents. In most cases the high-card range and the quality of the suits are not specified. A partnership should specify such limits, which will depend on the strength of the enemy 1NT, vulnerability, and position at the table. Any intervention against 1NT is dangerous inasmuch as the opener has shown a balanced, defensive hand. The danger applies to intervention in fourth seat as well as in the direct seat. After 1NT and two passes, fourth hand knows that the opponents have at most 23 HCP or so, but the pass on his right means that that opponent also probably has a roughly balanced hand. If fouth hand bids, therefore, there is some evidence that his partner will be short wherever he himself is long. At pairs scoring, playing 1NT not vulnerable seldom gets a bad board. Minus 100 beats the 110 or more that the other side usually could have made. When 1NT is bad, it is because the hand belongs to the side playing it, but others are in a suit (usually a major), making an extra trick or two. This is one reason to emphasize major suits in setting up a system of intervention against 1NT. Textbooks all mention the double of a 1NT opening, because they must distinguish it from the takeout double of a suit opening. If the double of 1NT were for takeout, it would require support for the unbid suits -- all four of them. It would therefore be a balanced hand, suitable for defence. So the double is for penalties. But such a double is rarely available and is a gamble even when it is. So, for many pairs, the double of a strong NT (16-18 or higher, usually 15-17 also) has some conventional meaning. Fairly frequent intervention, usually beginning with a double, is necessary after a weak NT opening. That is because the hand often belongs to your side, sometimes at the game level. Some constructive sequences are needed, in particular when you hold a powerful unbalanced hand on which a double would be worse than futile. It is not enough to set down a table of conventional intervening bids. A pair must go over the kinds of hands on which they will double or bid later in the auction. Two examples: S W N E 1NT P 2C/2H ? As the bid by N might be based on nothing, East must often act, even with less than ideal distribution. S W N E 1NT Dbl 2D ? East may have the balance of strength but no clear bid. It is reasonable to treat a pass as forcing over 2 of a minor after partner's double. ;Astro Astro is named for (and by) its inventors Allinger, Stern, and Rosler. Over 1NT, either directly or in the balancing seat: 2C: Hearts and a minor, 12+ points 2D: Spades and another suit, 12+ points Double and all other bids: Natural Responses to 2C: Pass or 2S: Long suit, no interest 2D: Denies 3 cards in the anchor suit (hearts) 2H: Signoff 2NT: 10+ points, asks for the other suit 3H: Invitational Responses to 2D: Pass or 3C: Long suit, no interest 2H: Denies 3 cards in the anchor suit (spades) 2S: Signoff 2NT: 10+ points, asks for the other suit 3S: Invitational If partner makes the relay response (2D over 2C or 2H over 2D) the first partner rebids: Pass: The relay response happened to be overcaller's second suit Two of the anchor suit: A good five-card suit or better. This rebid is preferred to a bid of the second suit. If responder rebids 2NT it asks for the other suit. New suit: A good suit at least 5 long. ;;Pinpoint Astro Pinpoint Astro is typical of several schemes for showing two-suiters more immediately. 2C: C+H 2D: D+H 2H: H+S 2S: Spades and a minor ;;Aspro This variant of Astro is due to Terence Reese. (Aspro is the name of a British brand of aspirin.) 2C may have 5S+4H. If the response is 2D, the overcaller then says 2S. With 4S+5H and a hand in the weak range, the bid is 2C followed by 2H over 2D. If stronger, the bid is 2D followed by 2NT. With 6-5 or 6-6: 2NT: C+S 3C: C+D 3D: D+H 3H: H+S With C+H or D+S, overcaller bids the minor, followed by a jump in a 6-card suit. A redouble by the overcaller is SOS. ;Brozel In the Brozel scheme, all 2-level interference bids show 2-suiters. Over an adverse 1NT opening, either in the direct or balancing seat: Dbl: One-suited hand. Partner passes or bids 2C (artificial) or bids an excellent suit of his own. 2C: C+H 2D: D+H 2H: H+S 2S: Spades and a minor. A response of 2NT asks for the minor. 2NT: C+D 3C/3D/3H/3S: 3-suiter, with the _other_ three suits. There is no natural double, so Brozel is of value primarily against a strong NT. ;Cansino The Cansino method is a loosened-up variant of Ripstra, intended to permit frequent intervention over a weak NT opening. Either in the direct or balancing seat: 2C shows support for C and two other suits 2D shows support for D, H, and S Dbl and 2H/S are natural Responses to 2C: Suits are natural in search of a fit. Jump suit bids are invitational with a suit playable opposite a singleton. 2NT asks for the short suit: 3C: singleton heart 3D: singleton spade 3NT: singleton diamond Responses to 2D: 3D is the only forcing response, asking for a four-card major. Other suit bids are as over over 2C. ;Cappelletti (Capp, Hamilton) Either in the direct or balancing seat: Dbl: Penalty 2C: A one-suited hand. Responder usually says 2D, which the 2C bidder will pass or correct. Responder may also pass 2C, bid 2 of a good 5-card major, or bid 2NT with a balanced 11-13. 2D: Both majors, at least 5-4. Responder usually bids his better major but may pass with long D or bid 3C with C. Responder bids 2NT to ask for opener's better minor, and when he wants to follow with an invitational raise in one of the majors. An immediate 3H/3S is preemptive. 2H: Hearts and a minor. A heart raise is preemptive. Responder bids 2NT to ask for the minor, and also when he wants to make an invitational 3H bid next. 2S: Spades and a minor. Responses are analogous to those for 2H. 2NT: Both minors ;D.O.N.T. The name stands for "disturbing the opponents' notrump". Dbl: Any 1-suiter, a transfer to 2C. Responder may bid an excellent suit of his own instead (7+ cards). With a balanced 14+ responder may pass. 2C: C and a higher suit. 2D asks for the other suit. 2D: D and a higher suit. 2H asks for the other suit. 2H: H+S. Responder usually passes or takes a preference to 2S. 2S: Natural, but weaker than the double followed by 2S. Since there is no natural double, DONT is useful mainly against a strong 1NT. The 2-suit bids show at least 5-4 and a minimum of about 8 HCP, depending on the score and on one's distribution. Responder, with 14+, may bid 2NT for clarification. Then: Overcall was Overcaller's rebid 2C 3C Bad hand, second suit still unspecified 3D Good hand C+D 3H Good C+H 3S Good C+S 2D 3C Bad D+H 3D Bad D+S 3H Good D+H 3S Good D+S 2H 3C Bad with better hearts 3D Bad with better spades 3H Good with better hearts 3S Good with better spades If the 2-suit bid is doubled: Pass: Tolerance for that suit Redbl: Asks for the other suit Suit: Natural and nonforcing If third hand bids at the 2-level: Dbl: Asks for the other suit Other: Natural and nonforcing ;Landy and Ripstra These were two of the early, rather limited ideas for intervening over 1NT. Landy is primarily for use against a weak NT. 2C is for takeout with at least 4 of each major. Responder: P or 2D: Weak with length in C or D respectively 2H/2S: Signoffs 2NT/3D: Invitational. 3H/3S: Also invitational but may be only a trebleton. 3C: The only forcing response, asking for clarification. In Ripstra, 2C and 2D show at least 4-4 in the majors, 3 or more of the minor being bid, and a singleton or void in the other minor. ;Suction Suction is a transfer overcall against 1NT which also looks after 2-suiters in touching suits, including S+C. Two of any suit shows the next higher suit or the _following two_ suits. I.e. 2C: D, or H+S 2D: H, or S+C 2H: S, or C+D 2S: C, or D+H 10+ HCP are normal in each case. Partner transfers to the next suit ("anchor suit") unless he has a very good suit of his own. The overcaller then removes to the next suit if he has the two-suiter.