Waiting 1♦
There have been many variants to unfold BAL 19+ at 1♣-1♦-1♥, such as Terrorist’s Moscito and Viking Precision. All these variants successfully rescue the 2NT opening from the notrump ladder, freeing 2NT up for preemptive uses. However, they tend to involve a cryptic relay structure at 1♣-1♦-1♥. I believe that 1♣-1♦-1♥ becomes too crowded when 1♣-1♦ is too negative.
In Blueberry Precision Club, 1♣-1♦ promises a suitable rebid to 1♥. The weak and relatively balanced hands go to 1♣-1♥.
| 1♣-1♦ | Waiting |
|---|---|
| 1♥! | F, 4+♥ or 19+ |
| 1♠ | 16–21, 4+♠ |
| 1NT | 16–18, BAL |
| 2♣♦ | 16–21, 5+# |
| 2♥♠ | 22–24, 5+# |
| 2NT | 22–24, BAL |
| 3♣♦ | 22–24, 6+# |
| 1♣-1♦ 1♥- | F, 4+♥ or 19+ |
|---|---|
| 1♠ | F, 4+♠ |
| 1NT | INV, 2–3♥ |
| 2♣♦ | INV, 5+# |
| 2♥ | PRE, 5+♥ |
| 2♠ | PRE, usually 6+♠ |
| 2NT | FG, 1–3♥ |
| 3♣♦ | PRE, usually 7+# |
| 3♥ | INV, 4–5♥ |
| 3♠! | FG, BAL 4=♥ |
| 3NT! | FG, UNBAL 4=♥ |