Opener's Game Force After Opening 1♠
The only time this is relevant is after the auction 1♠-1NT. The main trick
is to use 3♣ALERT to force 3♦ALERT which allows us to distinguish between 5=5
and 5=4 in the majors.
- 3♣ALERT then 3♥ - 4 exact hearts
- 3♣ALERT then 3♠ - spades only
- 3♣ALERT then 3NT - implies clubs but tolerance for NT
- 3♦ - diamonds
- 3♥ - 5(+) hearts