In the vernacular of the gurus and in angusj's overview of his Simple SuDoku program, the word "symetry" seems to command an certain respect in SuDoku puzzles --

-- Of the admittedly-few I've done, even the fiendish" ones in Gould's book, very few hinted of any symetry at all, neither in the initial nor the final number patterns

- What is it's significance? How does one recognize it?

-- Any simple example of symetry?

I did search but I apologize if I've missed something dumbly obvious.

(neat site)

Elroy

BTW, I meant to include that I also saw no particular symetry in the number of digits (0-9) represented (ie: some puzzles start without some of the digits) nor in the final candidate-pairs immediately prior to chaining-out the final solution.