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