Grand slam force Grand slam force The Grand Slam Force is a bidding convention in contract bridge that was developed by Ely Culbertson in 1936. It is intended to be used in cases where the combined hands of a partnership are so strong that a slam (winning at least 12 tricks) is a near-certainty and a grand slam (winning all 13 tricks) is a possibility. It allows one partner to gain information on the quality of trumps in the other partner's hand. When this convention is in force, a bid of 5NT (five notrump), when it does not conflict with other conventions used
Hand evaluation excess of 3 in the suit; for short suits only clear winner combinations are counted: An Acol strong 2 of a suit opening bid is made on 8 playing tricks (Landy 1998) This statistically derived method for evaluating Contract Bridge hands was developed by Zar Petkov. It attempts to account for many of the factors outlined above in a numerical way. A key differentiator between the bidding effectiveness of experts versus laymen is the use of hand visualisation during all stages of bidding. In his book "The Secrets of Winning Bridge", Jeff Rubens advises to focus on just a few