As I expected, the Outside gave me the most trouble, but only because I was missing an obvious digit placement for way too long.

Thanks for the gifts!

Outside is a type (like say skyscrapers or easy as ABC) where it really pays to cross off the clues once you've spent them. I was testing a puzzle that I thought was valid (this one actually) on the plane, completely missed an outside constraint I had not yet used, and was frustrated I wasn't remembering to cross off the used clues.

I wish I could blame not crossing off clues, but sadly, that's one thing I manage to do correctly. No, this was simply a digit that had to go somewhere because of basic row and column elimination.

The Outside looks rather like how I annotate placements that are in the grid (with a thought process of "I know there's a 7 in R3N1 but I don't know where"). Except I also write notes like that with a bit of a gap away from the edge to annotate placements in the middle box.

I still do "Outside" clues much like greg mentions -- it was probably my first ever type of notation. I'd never had a way to make them work in the central nonet and am probably too set in my ways to try the extra gap method. But it's a good plan.

@motris: Do you suppose there would be any interest in running a "guerrilla" style mini-Cup thing in Philadelphia? I would envision it as...anyone interested in playing would craft a fancy sudoku -- possibly a new variant, possibly a version of an underrepresented style, ideally not some mundane style -- and would bring a few dozen copies. Everyone who wanted to take part would get a copy of each puzzle and would either time themselves or be part of a larger congregation of solvers meeting at some arranged time. The author of each puzzle would collect everyone's efforts and grade them, and overall rankings could be compiled via "least total time" or "lowest combined rank over all puzzles" or possibly some hypothesized-to-exist grand prix point scoring system I've still yet to type up.

I realize my team participation is by no means a given, but I anticipate being in Philadelphia as a competitor or as a volunteer/grader. As for your participation -- if you find the WPF still too frustrating when it comes to official sudoku competitions, maybe this unofficial offshoot would be a nice diversion to go with your contributions as an author of some WSC puzzles? That assumes that anybody would be interested, although it sounds like what's asked of competitors (writing one fantastic puzzle) isn't too high a hurdle compared to the reward (playing on many fantastic puzzles). With the right people being told, I can see it being a pretty popular and neat, if informal, little diversion.

As for coordinating -- I'd be happy to do what little would be required of it, assuming I'm in the Illadelph at WSC time, which seems pretty likely, one way or another. I imagine this would just require gathering people here and there and preventing anybody wearing a hoodie from playing, so it shouldn't be too much work.

Thanks for the puzzles. Assuming the TSA doesn't require everyone to wear handcuffs from takeoff to touchdown, I'll be trying some of your recent efforts on my flight from PHX to ABQ.

I've long been interested in a sudoku equivalent of the 24 hours competition. What you are proposing is even simpler, as only one or two puzzles would be brought by each competitor. I do question if there are enough constructors who compete to get a good nucleus of a competition going; I also wonder if the organizers are planning fun evening activities which would take the time one could use for these puzzles (I'm imagining a WSC-equivalent of what the Turks did with Paint by Numbers and Sudoku in Antalya or the Hungarians did with popular music and word puzzles in Eger).

Oooooh, a Thomas Snyder Sudokurve... I need to get my butt in gear and finish making puzzles (for the Hunt) so I can start solving them again. ...Withdrawal shivers... - ZM