Quiz 4 (precision auction) original problem:
Is South’s double comparable to the initial 1♦️ bid?
Solution–
In this precision auction the 1♦️ bid and the double are both strength showing only. South’s double specifies a subset of the hands indicated by the withdrawn 1♦️ bid. Under part two of the definition this makes the double comparable. Notice that the substitute call is more specific and the illegal call is less specific.
