# Expert Reviews

Andrew Stuart

8/14/12     Pattern Enumeration       Stuart’s pattern lettering and freeform technique examples are adapted from Logic of Sudoku. Stuart produced good examples, but did little else with these fundamental ideas.

11/06/12  Digital Forcing Chains?  Stuart’s arbitrary choices of bv and value can generate an almost nice loop, and when it becomes a “Digital Forcing Chain”, it has done that. It’s simple trial and error.

11/13/12  Nishio Forcing Chain?     Doing the guess, and carrying it out by an AIC, changes nothing.

11/27/12  Cell Forcing Chains           Exploring what every candidate in an arbitrarily chosen cell “sees” via forcing chains is obviously not a practical option for humans.

12/11/12  Unit Forcing Chains        A similar humanly impractical idea. Its reverse is sometimes recognized, when a candidate is seen to remove all candidates of a number from a unit.

Tom Sheldon

2/05/13   Grading the Master Class     Calls out the hyped title, citing the actual level of instruction offered.

2/12/13   Tom Sheldon on Sudoku Solving   Disputes pronouncements, and critiques unexplained theorems

Paul Stephens

4/9/13     Starting With Stephens           From Week to Week and Sudoku Addict’s. Bypass, then a long number scan for candidates, with no slink marking.

4/16/13   Advanced Stephens              Just subsets and boxline. Beyond is “extreme”.

4/23/13  A Bv Scan of Week 48     Demonstrating some of what Stephens misses.

4/30/13  Extreme Stephens             Advanced Sysudoku, but without Sue de Coq, APE, Medusa coloring or AIC, and limited to regular fish. Then Nishio.

5/14/13  To Nishio or Not to Nishio   Using Nishio to survey for grouped ANL

Allen Barker

11/19/13 Pulling Rank                   Explains rank = 0 example as and AIC ANL.

11/26/13  Higher Rank Theory     Explains rank > 0 and identifies SudokuOne rank = 3 example as a quadruple Stuart cell forcing chain.

12/03/13 Rank’s Little Gotcha     Rejects setlink mixed rank theory for human solving. Displays Barker’s GN first removal SLG, with about 50 remaining for the solution.

Bob Hanson

6/03/14   Hanson’s Sudoku Assistant      Hanson’s “generalized method”

6/10/14   Basic Solving with Bob               Completion strategy, singles and boxline

6/24/14   SA Finds Locked Sets            Sysudoku covers what Hanson leaves unexplained.

7/01/14   Bob Goes Regular Fishing           Hanson’s grid analysis, with many errors. Student Assistant uses the suset algorithm .

7/08/14   Bent Naked What?                   Hanson’s explains the XY-wing and XYZ-wing using a complex strategy he claims to explain later. It’s not a subset, as Bob labels it.

7/15/14   Hanson’s Bent Naked N-Set     Sysudoku explains and renames the complex strategy, proving Bob’s BSN1 and BSN0 rules. Applications other than the wings have not turned up.

7/22/14   SA ALS Toxic Sets                       Single common ALS toxic sets and double common locked set. The latter is new.

7/29/14   Finned Fishing with ALS         Catching finned fish by ALS, by the suset algorithm.

8/4/14     Checkpoints on Suset ALS Kraken Fish   Amazing f sashimi and kraken fish by suset analysis on Hanson’s example. Bob doesn’t kraken.

8/11/14   Hanson’s Polarity ANL       A defined method crafted from Hanson’s Almost-Locked Range, best applied with coloring.

8/18/14   Hanson’s Strong and Weak Hinges     Gives up on Hanson’s muddled chain theory and explains hinges logic as AIC

Peter Gordon

9/30/14  Gordon’s Basics Guide   Singles search, with dublex and cross-hatch, then number scanning, subsets and boxlines by example. Then an awkward slink marking.

12/02/14 Gordon’s Fishing Guide     Offers no help on regular fish, and doesn’t cover anything else.

12/09/14 Gordonian UR-ology         Gordon’s renamed, though already well-known UR methods.

12/16/14 A Gordonian Fantasy       Gordon’s loosely described Gordonian Polygon is defined for him.

12/23/14 Plus and One-Sided UP     The Unique Polygon is defined (and renamed) to include Gordonian Plus and One-sided variations.

12/30/14 Extended Gordonian Overreach   Gordon’s renaming of extended UR and his imaginary “Gordonian Rectangle Wing” are rejected.

1/13/15    Wings and Chains With the Guide   XY-wing as a forcing chain, regular XYZ-wing with an incomprehensible “buddies” rule, a formula for turbot fish, nothing on X-chains.

1/20/15   Cycling Blindfolded          Equally overspecialized and inept on AIC, and “bilocation graphs”. obsolete by coloring. Omits XY-chain ANL.

Denis Berthier           So far, scattered comments and no overall assessment.

12/27/11 xyt-chains                           A way to start an XY chain. The post defines a “skip rule” to prevent the extended XY-chain from becoming a truth net, an aid for trial-and-error.

3/06/12  XY-loops “are useless”     Berthier gets wrapped up in restrictive definitions and loses his way on XY-loops, missing a very useful human solving tool.