Also, the success rate for a game contract in a major suit when a partnership has a combined holding of 26 points[4] and eight cards in the major is about 80%, whereas a game contract in 3NT with 26 high card points (HCP) has a success rate of only 60%, or 50% with 25 HCP; the success rate for a minor suit game contract when holding 26 points is about 30%.
[5] Accordingly, partnership priority is to find an eight card or better major suit fit when jointly holding sufficient values for a game contract.
After an opening bid or an overcall of 1NT (2NT), responder or advancer bids an artificial 2♣ (3♣) to ask opener or overcaller if he holds a four- or five-card major suit; some partnership agreements may require the major to be headed by an honor of at least a specified rank, such as the queen.
By invoking the Stayman convention, the responder takes control of the bidding since strength and distribution of the opener's hand is already known within a limited range.
A notrump bidder who has at least four cards in each major suit normally responds in hearts, as this can still allow a spade fit to be found.
In the standard form of Stayman over 1NT, the responder has a number of options depending on his partner's answer: Over these bids, the notrump bidder (1) with a maximum hand (17 HCP), goes to game over an invitational bid and (2) with four (or more) cards in each major suit, corrects to the previously unbid major suit.
Some partnerships also admit responder's rebids of a major suit that the notrump bidder did not name.
For example, if South opens 1NT, and West overcalls 2♦, North, if he has adequate values, may call 3♦, invoking Stayman.
Alternatively, North, if his hand lacks the values for game in notrump, may double, which by partnership agreement employs Stayman.
Partnerships who have not yet learned Stayman but choose to adopt Stayman (without having yet learned or having chosen not to use Jacoby Transfers) will need to adjust their use of normal two-level responses after a 1NT opening, because the availability of this convention changes the nature of what had been normal 1NT responses.
If opener has maximum values, a fit, and strong support, he may raise to the 3-level, but under no circumstances may he take any other action.
For example, if responder has a short suit and wishes to know if opener has four-card cover in it, so as to play in no-trumps.
If opener shows hearts initially, 2♠ can be used to find a fit in spades when the 2♣ does not promise a four-card major.
The Smolen convention provides an alternative method to show a five-card major and game-going values.
If opener rebids a major suit you have found a 4-4 fit and ability to trump club losers.
Likewise, a response of 2♦ guarantees no worse than a 5-2 fit in diamonds and, with a fifth trump, a potential additional ruff.
This allows responder to effectively bid hands which are 5-4 in the majors, by looking first for a 4-4 fit and, if none is found, signing off in his 5 card suit.
If Jacoby transfers are not played, there are two approaches to resolve the situation when responder has a 5-card major but only invitational values.
In the original Precision Club system, forcing and non-forcing Stayman are differentiated in the start: 2♣ by responder shows only invitational values (and the continuation is the same as in basic Stayman), while 2♦ is forcing to game (responder bids 2NT without majors).
Relay bids over opener's rebids of 2♦, 2♥, 2♠, 2NT, 3♣ allow shape to be defined further if attempting to find 5-3 major fits.
Relay bids over opener's rebids of 2♦, 2♥, 2♠ allow shape to be defined further if attempting to find 5-3 major fits.
Relay bids over opener's rebids of 2D, 2H, 2S allow shape to be defined further if attempting to find 5-3 major fits.
Developed to be used in combination with following other responses to 1NT: 2D, 2H Jacoby transfers to majors; 2S range finder/transfer C; 2NT invitational hand with 5,5 minors 10-11 HCP.
After completion of the transfer, bidding the other major at the three level shows four cards in it and a game forcing hand, in line with the 1NT - 2♣, 2♦ structure above (1NT - 2♦, 2♥ - 2♠ = invitational 5♥-4♠).
Initially developed by Neil Silverman and refined by Kit Woolsey and Steve Robinson in 1977-78,[8][9] is a variation of the Stayman convention designed to find a 5-3 fit in a major, augmenting the search for a 4-4 major fit by standard Stayman.
Over a 2♦ response, rebids by responder are intended to disclose his distributional features in the majors as well as his strength.
The original 1977[8] and 1978 revised[9] rebids described by Woolsey are tabulated below: Opener and responder continue the bidding having a clearer understanding of each other's distributional features and are better positioned to select the ultimate denomination and level of the contract.
Many variations to the Puppet Stayman bidding structure have been devised since Woolsey's 1978 summary; partnership review and agreement on the preferred modern treatment is required.
Responses by opener shows the following: Partnership agreement is required on how to handle the case of holding four of the other major and three of partner's suit.