dailysudoku.com

thanks keith... been making that mistake a lot recently. wings are a lot easier to find once boxes are properly swept.

+---------+------------+-----------+
| 89 3 7 | 2 6 18 | 5 19 4 |
| 89 6 2 | 4 18 5 | 3 7 19 |
| 5 4 1 | 7 3 9 | 8 6 2 |
+---------+------------+-----------+
| 6 59 ...

awesome, norm. i figured i was missing something simple like that, and it usually is that simple when i stare at a puzzle for hours. thanks.

the empty xy wings were mostly because i already caught ...

+------------+-----------+-----------+
| 79 3 579 | 6 2 1 | 8 4 57 |
| 27 4 1 | 3 58 58 | 26 9 67 |
| 8 25 6 | 9 7 4 | 12 13 35 |
+------------+-----------+-----------+ ...

Check your 5s in boxes 7/8/9. That should clear some things up.

Stupid question: how does the 4 in r3 confined to box 3 then unlock the 4 in r7c1? I still have possibilities for 4s in r7c3 and r2c1.