Brays Learning Curve: Run or Prime?

Money Play. How should Red play 63?

2018 - Intermediates 8

XGID=-a-BBCCBA———ccbbcBa-:1:1:1:63:0:0:3:0:10

 The age-old question: should you build the full prime with 8/2, 5/2 and perhaps crack it as soon as next turn, or use that precious 6 to run with either 23/14 or 22/17, 8/5?

When I had this position as White, I knew what I wanted my opponent to do and that was to run. He very kindly obliged and after a couple of good rolls I was actually able to play on for, and win, a gammon.

The correct play by quite some way 8/2, 5/2 – see the rollout below. The keys to the position are:

  • A full prime is much stronger than a five-point prime and even if Red cannot escape a checker next turn, he will still probably have a five-point prime, so he will be no worse off and, if he rolls a six, he is nearly home free.
  • Crucially, White must play before Red rolls again and facing a full prime he will have to move on his side of the board. Big numbers like 64, 65, 55, 54 etc now severely damage his position, giving Red gammon opportunities.

My rule of thumb in such positions is to take the full prime if it is on offer and that rule has stood me in good stead throughout my playing career. If Red had a 65 to play then 23/27, 8/3 would be correct.

Note that 23/17, 8/5 is much better than 23/14 because it halves the gammon losses. The former is an error, the latter is a blunder. Players often forget to take gammons into account properly when deciding upon a move. 23/14 exposes three blots and that is too many when there is a sensible alternative.

So, remember, hardly ever turn down a full prime!

Rollout Information from Extreme Gammon

Intermediates 8 rollout

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Comments

  1. Michael Agranoff Michael Agranoff says:

    I think the point is that Red should make the prime because he has better timing. White is more likely to crash first. Otherwise, it would be better to run.

  2. Frank DiMaggio says:

    “My rule of thumb in such positions is to take the full prime if it is on offer”. on offer ?

  3. Jeff Spencer says:

    Thanks Cris. Your Learning Curve series always provides keen insights or at the very least brings clarity to ideas that I’ve understood intuitively.

    There are two typos in this article you may want to fix:
    1) “or use that precious 6 to run with either 23/14 or 22/17, 8/5?” —-> “or use that precious 6 to run with either 23/14 or 23/17, 8/5?”
    2) “then 23/27, 8/3 would be correct.” —-> “then 23/17, 8/3 would be correct.”

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