Natural 1♠
The major suit openings show 11–17 points and 5+ cards. I separate them into two chapters due to subtle differences in their continuations.
- Unpassed 1♠-1NT is forcing.
- Maggie 1♠-2♣ is either a natural game force or a heart invitation.
- Fit-showing jumps show mixed raises.
- For choice between 4♥♠, 1♠-3♥ expresses an invitation with 36(xx) rather than mixed raise with 45(xx).
| 1♠- | 11–17, 5+♠ |
|---|---|
| 1NT | F, usually 7–11, 0–3♠ |
| 2♣! | NAT FG or INV 5–6♥ |
| 2♦ | FG, 4+♦ |
| 2♥ | FG, 5+♥ |
| 2♠ | CONST, 3+♠ |
| 2NT! | FG, 4+♠ |
| 3♣♦! | CONST+, 5+#, 4+♠ |
| 3♥! | INV, 6+♥, 3=♠ |
| 3♠ | LIM, 4+♠ |
| 3NT! | COG, 12–15, 33(43) |
| 4X! | SPL, 0–1#, 4+♠ |
| 4♠ | PRE, UNBAL 4+♠ |
Responding with 5+ hearts
- Game-forcing: 2♥
- Strong invitational 6+ hearts: 1NT and then 3♥
- Invitational: 2♣
- Constructive: 1NT and then 2♥
P-1♠
P-1♠ reduces to a fairly natural system. We can keep using Stenberg 2NT because it assigns minimum hands to 3♣.
| P-1♠- | 11–17, 5+♠ |
|---|---|
| 1NT | NF, usually 7–11, 0–3♠ |
| 2♣♦♥ | INV, 5+# |
| 2NT! | INV, 4+♠ |