Five-card majors for offensive purposes. However, if the trump cards break 4-1 or 1-4, then drawing trump will result in no trumps left for offensive purposes. The value of five-card majors can be understood then on two levels: But five-card majors have several drawbacks: Both partners must agree to follow the five-card major bidding treatment on their opening bid. Opener must have at least five cards in hearts or spades to start the bidding with that suit. Responder is expected to show support with three-card support, indicating an eight-card fit. With only four cards in a major suit, the opening bidder is
Vanderbilt Club summary, Vanderbilt Club is: Vanderbilt distinguishes between informatory doubles and business doubles, two expressions known from auction bridge. Doubles should be informatory at the one-level; at the two-level if neither you nor your partner has previously bid; and perhaps at the three-level, depending on the player's judgment of the score and the bidding. Doubles should be made more freely in contract than in auction bridge, because the potential profit is greater. Vanderbilt does not otherwise discuss bidding in contested auctions. Vanderbilt describes three types of invitations to slam: bidding more than is needed to score game; bidding the opponents' suit;