Direct Hidden Triplet
Direct Hidden Triplet combines a Hidden Triplet elimination with the single it immediately creates. 3 digits have possible positions whose union is exactly 3 cells in one sector; the digits do not need identical candidate distributions.
What is Direct Hidden Triplet?
First establish the Hidden Triplet by counting the union of the selected digits’ positions. Remove other candidates from those 3 reserved cells. If that removal leaves another digit with one possible position in a sector, report the resulting Hidden Single placement as part of the same direct deduction.
How to spot it
Track positions for each digit rather than searching only for 3 identical candidate lists. After finding a 3-digit/3-cell union, apply its internal eliminations and check affected rows, columns, and boxes for a digit reduced to one position.
The logic
The hidden subset reserves its 3 cells for its 3 digits, so other candidates leave those cells. If one of those removals leaves a digit with a single position in any affected sector, that candidate is true. The direct name combines these two sound steps.