Grid technique · Beginner
False Transposition
Carrying a confirmed elimination from one mini-grid into another that shares a category with it.
Why it works
If Mina isn't the florist, and Mina is confirmed in the red house, then the florist isn't in the red house either — the elimination travels the same way a confirmation does.
Trigger
A no-mark in one mini-grid, once the row or column it is in has a confirmed yes elsewhere.
Common mistake
Transposing true marks but forgetting that eliminations transpose exactly the same way, just slower to notice.
Example
Mina isn't the florist, and Mina is confirmed in the red house, so the florist isn't in the red house either.