Game 6, move 8 : Forum 5-1

[diane]

It is almost a good roll, but when you come to play it....hmmm    Well, a lot of options there, but there are more - so tell me if you want another one...

Forum, blue, to play 5-1

bJttgABYz4UBMA:8Im0ACAAIAAA

[ah_clem]

Spoiler

I don't think there's much alternative but to hit the blot. If we don't hit, he'll almost certainly escape next move.

So that narrows it down to two moves.  One leaves four blots and abandons the midpoint.  The other leaves only two blots and leaves the midpoint intact.  Seems like an easy choice. 9/4, 8/7*

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[vikingblood80]

Spoiler

We definitely need to play safe here. We are on GS (Gammon Safe). A gammon will cost us a whole game that rkb needs to win less. Only about half of the rolls let rkb escape his last man. (2-5,2-6,3-4,3-5,3-6,4-5,4-6,5-6,4-4,5-5,6-6) 19 rolls and 5-6 being not very pleasant. If it were DMP and only winning or not would count I would also hit, but here gammon costs us too much.I think we would be better of not hitting may be waiting for a later chance or even let this crawford game go instead of risking losing gammon.  
9/4 6/5

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[ah_clem]

Spoiler

We definitely need to play safe here. We are on GS (Gammon Safe). A gammon will cost us a whole game that rkb needs to win less.

Gammons cost us almost nothing.  If rkb wins a single point, we're 4-3 post Crawford, he'll double immediately and we play the next game for the match. If rkb wins a gammon, it's 4-4 and we play the next game for the match.  Either way, we lay the next game for the match, the only difference is that we get a free drop if he wins a single point.  That's not much of a difference.

Gammons don't matter.  It's not "Gammon save" but DMP that's afoot.

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[stog]

Spoiler

8/7*,9/4 for me then the 6666 that aid talked about! but that doesn't cover ..eek

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[dorbel]

Spoiler

Another tough play, which highlights the good play made by rkb last turn. Had he stayed back passively, we wouldn't have had a problem. Not hitting might be right, as there are 20 (!) rolls for White that leave a direct shot next turn, in addition to 5-2 and 4-3 which leave two indirects. If we choose not to hit, then we play 9/4, 6/5, or possibly 8/3, 6/5. I know that that leaves a shot but it is very creative! I wouldn't argue much against either play if a partner was hot for the quiet approach, but waiting looks too passive to me and I think that we bite the bullet and go for it. I prefer 13/7* to 9/4, 8/7*. It's only two extra return shots, for which we get an extra checker into the zone, more covers for the 5pt and the bar slotted. It does expose four blots and raise the awful spectre of a match-losing backgammon, but that's a long way off yet.

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[ah_clem]

Spoiler

Another tough play, which highlights the good play made by rkb last turn. Had he stayed back passively, we wouldn't have had a problem. Not hitting might be right, as there are 20 (!) rolls for White that leave a direct shot next turn, in addition to 5-2 and 4-3 which leave two indirects. If we choose not to hit, then we play 9/4, 6/5, or possibly 8/3, 6/5. I know that that leaves a shot but it is very creative! I wouldn't argue much against either play if a partner was hot for the quiet approach, but waiting looks too passive to me and I think that we bite the bullet and go for it. I prefer 13/7* to 9/4, 8/7*. It's only two extra return shots, for which we get an extra checker into the zone, more covers for the 5pt and the bar slotted. It does expose four blots and raise the awful spectre of a match-losing backgammon, but that's a long way off yet.

I'll have to take your word on the non-hitting plays.  They just seem weak and ineffectual to me.

As for choosing which hitting play to make, you have a very good point.  13/7* leaves us in a more flexible position as long as we're not hit.  It only adds 6-3 as hitting numbers vs. the play I suggested (5-4 already hits, and four checkers back isn't much worse than three, possible it's stronger)  Is the additional flexibility worth the extra risk?

I'm not seeing that it's clearly worth it.  It might be, but let's assume he enters on the three and doesn't hit anything - with my play I've got 5 points with spares or blots. that bear on his blot. That should be enough to clobber him again.  If he enters on the one or two point, the blot on the 9 is out of reach for hitting.  Granted, it's well poised to fill in the prime.... maybe that's the key - I'm thinking hit hit hit, while you're thinking prime.  And given the layout of his side of the board, our best chances are to have his runner stuck behind a prime rather than stuck on the bar.

So, I need to reevaluate the position in terms of prime-making plays rather than pointing on the runner.  For that, leaving a checker on the 9 is stronger. Moving it to the four when the 5 and bar points are not made is anti-thematic.

Ok.  You've convinced me.  Appologies for thinking out loud, but sometimes that's what I need to do.  I'm going to change my vote to 13/7*.

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[vikingblood80]

Spoiler

Gammons don't matter.  It's not "Gammon save" but DMP that's afoot.

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Spoiler

Ah correct...changed my vote.

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[stiefnu]

I'm going to change my vote to 13/7*

Me too.

[adrian]

9-4/6-5 and waiting for 66 followed by more 66 or 55 

[diane]

ok, well it is looking more decided now - I will move it along this evening - so tell everyone time is almost up to make any more arguments 

[ah_clem]

Spoiler

Thanks to Dorbel we chose the best move again.  The other hitting play is a .03 error.  The "safe" plays are .04 errors and up.


    1. Rollout          13/7*                        Eq.:  -0.541
       0.272 0.054 0.006 - 0.728 0.411 0.029 CL  -0.541 CF  -0.541
      [0.002 0.003 0.001 - 0.002 0.003 0.002 CL   0.007 CF   0.007]

    2. Rollout          9/4 8/7*                     Eq.:  -0.572 ( -0.030)
       0.242 0.044 0.004 - 0.758 0.357 0.016 CL  -0.572 CF  -0.572
      [0.002 0.002 0.001 - 0.002 0.003 0.002 CL   0.005 CF   0.005]

    3. Rollout          8/3 6/5                      Eq.:  -0.583 ( -0.042)
       0.225 0.034 0.003 - 0.775 0.236 0.009 CL  -0.583 CF  -0.583
      [0.002 0.002 0.001 - 0.002 0.003 0.001 CL   0.004 CF   0.004]

    4. Rollout          9/4 6/5                      Eq.:  -0.598 ( -0.057)
       0.212 0.041 0.004 - 0.788 0.176 0.006 CL  -0.598 CF  -0.598
      [0.002 0.003 0.001 - 0.002 0.003 0.001 CL   0.004 CF   0.004]

    5. Rollout          6/5 6/1                      Eq.:  -0.645 ( -0.104)
       0.194 0.024 0.001 - 0.806 0.251 0.008 CL  -0.645 CF  -0.645
      [0.002 0.002 0.000 - 0.002 0.003 0.001 CL   0.005 CF   0.005]

    6. Rollout          9/3                          Eq.:  -0.664 ( -0.123)
       0.182 0.029 0.003 - 0.818 0.191 0.008 CL  -0.664 CF  -0.664
      [0.002 0.003 0.001 - 0.002 0.003 0.001 CL   0.004 CF   0.004]
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[vikingblood80]

Ah interesting..did not see that. Not hitting seems to be wrong but not to be a blunder.