IMP/Precision/MeckwellPrecision
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The 1C Club Opening
The 1C opening is normally 17+HCP with a balanced hand, or 16+ with an unbalanced hand.
- All responses other than 1D are game forcing and promise 8+HCP.
1D - artificial negative, 0-7HCP, may be any shape
1H - either 1) 5+ spades, 8+HCP, or 2)11-13 balanced.
1S - shows 5+ hearts, 8+ HCP.
1NT - shows, 5+ clubs, 8+ HCP.
2C - shows 5+ diamonds, 8+ HCP
2D - balanced hand, 8-10 HCP.
2H - balanced hand, 14+ HCP.
2S - three suited hand, with specifically 1444, 4144, 0445, or 0454 shape, 8+ points
2NT - three suited hand, with specifically 4414 or 4441 shape
3C to 4C - show specific 3 suited patterns (4441 or 4450) and strengths, not including a 5 card major (5M4x4y hands always respond to show the major).
The response structure is such that in all but a few cases, opener can arrange to play game or slam in his own long suit or responders suit or no trump. Three suited hands or 8+ HCP were handled in the original Precision system by initially responding 1 and then making a special jump rebid (the impossible negative or unusual positive). Meckwell handle these cases with an immediate positive three suited response from 2 thru 4. Although these responses are unique to Meckwell, conceptionally the transfer principle is used in main other systems in responding to 1.
What is really unique is the rebid structure by opener. If you are willing to accept artificiality, the advantages of using switch rebids immediately becomes clear. Let us first consider openers problems after a 1 response (spades or 11-13 balanced). If opener is balanced (or semi-balanced with no weak doubleton or singleton other than perhaps spades, he can rebid 1NT. This method is economical and efficient with pattern that include say 4 hearts and a 5 card minor and limited values. If openers main suit is spades, or he has some kind of spade fit, he can rebid 1 (leaving plenty of room to show any two or three suited hands. The remaining hand types include mostly one suiters or two suiters in the minors or hearts. Since it is normal to show the higher ranking suit first with two suiters, a natural rebid of 2 would include more hand types than a 2 rebid showing clubs. This is an inefficient use of bidding space, it is better to use 2 to show hearts (plus a possible second lower suit) and a 2© rebid to show clubs (nearly always one suited). Note that in this auction the declarer for all club and heart contracts has already been determined, so that is not a consideration in the design of a rebid structure. We are left with the following: