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Secondary back checker principle

Posted By: Nack Ballard
Date: Wednesday, 28 July 2010, at 3:59 a.m.

In Response To: Rollouts and Comments (Paul Weaver)

Great comments as usual, Paul. I hope you find time to grace us with more of your fine analysis.

It's nice to see that your (more reliable) full rollout results agree with my two old truncated rollout results (where the middle position has a .002 margin between H and @.) I had never considered the third position (62S-64H-52) but I found it trivial to determine the correct answer by applying what I have discovered from other position pair/trio comparisons:

A key principle in this type of hit-or-anchor decision is how advanced one's secondary back checker is. In Paul's trio, after playing the obvious portion of the move, his secondary back checker is on the 22pt, 21pt and 20pt, respectively, and (with the other half of the roll) hitting is wrong, tied and best, respectively.

Below is a position trio from my "Anchor or Hit with 54?" article (published in the ChicagoPoint a few years ago). In all three cases, Blue has entered with a 5 and has a 4 to play.

When the secondary back checker is on the 24pt, hitting is wrong. (Hitting is also wrong if the 10pt checker is back on the midpoint; i.e., if Blue had played opening 31D instead of 43D.) When the secondary back checker is on the 23pt, hitting is tied. When the secondary back checker is on the 21pt, hitting is best.

43D-62H-54 (lone 4 to play): @ is best

41S-62H-54 (lone 4 to play): @ and H are tied

43Z-62H-54 (lone 4 to play): H is best

The basic idea is that in subsequent play -- especially in an ensuing exhange of hits, Blue's chance of making an advanced anchor is directly related to how far his secondary back checker has advanced and therefore inversely related to the urgency of anchoring now. It works the same way both in Paul's trio and in the sample trio from my article (illustrated above).

Nack

Messages In This Thread

• 64S-62H-43, 63S-63H-43, 62S-64H-52
  Paul Weaver -- Tuesday, 27 July 2010, at 12:06 a.m.
  • 64S-62H-43, 63S-63H-43, 62S-64H-52
    Nack Ballard -- Tuesday, 27 July 2010, at 5:21 a.m.
  • 64S-62H-43, 63S-63H-43, 62S-64H-52
    Sam Pottle -- Tuesday, 27 July 2010, at 5:24 a.m.
  • Rollouts and Comments
    Paul Weaver -- Tuesday, 27 July 2010, at 5:38 p.m.
    • Rollouts and Comments
      David -- Tuesday, 27 July 2010, at 6:34 p.m.
      • Rollouts and Comments
        David Rockwell -- Tuesday, 27 July 2010, at 7:22 p.m.
        • Giving Seminars
          Paul Weaver -- Tuesday, 27 July 2010, at 7:28 p.m.
          • Giving Seminars
            neilkaz -- Wednesday, 28 July 2010, at 2:56 a.m.
      • Strongly Recommeding the Tournament in Madison over Labor Day
        Paul Weaver -- Tuesday, 27 July 2010, at 7:22 p.m.
        • Strongly Recommeding the Tournament in Madison over Labor Day
          Bill -- Tuesday, 27 July 2010, at 7:44 p.m.
    • Rollouts and Comments
      Martin -- Tuesday, 27 July 2010, at 7:51 p.m.
      • Rollouts and Comments
        Paul Weaver -- Tuesday, 27 July 2010, at 8:18 p.m.
    • Secondary back checker principle
      Nack Ballard -- Wednesday, 28 July 2010, at 3:59 a.m.