Today's puzzle isn't a valid puzzle. There's a unique rectangle that is pure 2/6 in all four cells. First time I've ever seen that happen here. http://www.learn-sudoku.com/unique-rectangle.\nhtml
That's funny, I didn't run into the UR. Are you sure it isn't reduced by another cell?
I'm looking at the final puzzle and it's right there. I don't want to spoil the puzzle for anyone by saying where they are though.
I don't see any unique rectangle where I can swap the 2s and 6s and not affect the 2s and 6s also in those bigger squares. There are at least three places where there is a square of 2 and 6, but none of them let you swap their places.
How odd... how is it we have differing solutions?
OK, SPOILER ALERT!! Read no further! The UR is in (upper left corner is 1,1) 5,5 5,8 7,5 and 7,8
OH, Ok. I get what you're saying.
And I see what my logical fallacy is. OK. Move along. Nothing to see here :)
Did you really get a second solution Andy? ... I have the lower left corner forcing the lower right corner and thus forcing that rectangle into a single solution.