Crane

 

The full value of the hand is bid immediately in accordance with point count. A hand containing 12-15 points is opened at the one level. Containing 16-19 at the level of two; 20-23 at three; 24-27 at four. Both opener and responder count a singleton as 3 points and a void as 6 points. Nothing for a doubleton.

This is also known as the

Common Sense System

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