ETA:


Is used after the impossible 2NT or 1D bid, depending upon the system (shows a 4441 distribution). You bid in a 4 card suit, not the singleton.
1. step: Jack fourth or worse.
2. step: 1 top honor.
3. step: 1 top honors + Jack.
4. step: 2 top honors.
5. step: All three top honors
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