dailysudoku.com

[George Woods]

Sorry, I clicked on New rather than reply and it is not worth a new section

This one along with some others I guess, reveal a Wing or some other "killer" solution before the fundamentals are completed. So I used the XY wing, inserted a 2 and then looked further and found some more moves that didn't apparently rely on the new 2. i.e. I was completing the fundamentals and on to a complete solution. So I wondered whether my solution was a lucky mistake or the real thing, so had to do it again completing the fundamentals before invoking the XY wing to a solution that depnded clearly on the XY wing and was thefore valid.

So this type of puzzle- although I had solved it correctly first time had me worried simply 'cos the wing revealed itself "too early"! in the solution!!!!!

[Mogulmeister]

Speaking empirically, I have noticed that you can sometimes spot something early on that collapses the puzzle but in the long run you might also chase that down and still be left with a lot of house cleaning to do !