BTU Namyats
BTU uses a 4X scheme that conveys ~0.58 more bits than traditional or Meckwell Namyats.
- 4♣: solid major suit without any outside A/K
- 4♦: semi-solid major suit with 0–1 outside A/K
- 4M: non-solid (1.5+ NLTC) major suit
| 4X- | PRE in 4M |
|---|---|
| 4NT! | RKCB |
| 5m! | CTRL ASK |
| 4X-5m- | CTRL ASK |
|---|---|
| +1 | No CTRL |
| +2 | K or singleton |
| +3 | A or void |
| 4♣♦- | (S-)SOL PRE in 4M |
|---|---|
| 4♦! | S/T (R) |
| 4M, 5M, 6M | P/C |
| 4♣-4♦- | S/T (R) |
|---|---|
| 4M | NAT MIN |
| 4NT! | MAX, CTRL in every side suit |
| 5♣! | MAX, no CTRL in ♣ |
| 5♦! | MAX, no CTRL in ♦ |
| 5M! | MAX, no CTRL in oM |
| 4♥- | PRE, non-SOL |
|---|---|
| 4♠ | S/O |