Doubling in holding games

The next simplest doubling situation is that of a holding game, which comes up rather frequently. Below is a prototype position:

You have escaped both of your backcheckers and have achieved full freedom. This grants you an enormous advantage towards winning the match. All that remains is to bring the remaining checkers on your midpoint home safely, and then you can cash in the victory. Meanwhile, Gary has secured a pretty good anchor, the 4-pt anchor, which allows him to hang back and wait for a turn-around shot.

Can you offer the cube yet? And if so, should Gary take?

The oversimplified conditions for a proper double in a holding game are:

  1. to be leading the race by 14 pips or more
  2. to have 4 or fewer checkers on the midpoint
  3. for your opponent to have all of their checkers in your homeboard on a single point

As for whether to take or pass, it’s a pass if the player doubling (blue) has already evacuated the checkers on their midpoint. Hitting those checkers really is Gary’s last kick at the can, so to speak. If the midpoint checkers are on the 12-pt, or on a point that’s 6-pips away from your anchor, it’s still a take, but any closer and it’s almost surely a pass. Aside from that, it depends on which anchor is being occupied. If it’s the 4, 5, or 7, and they still have control of their midpoint (the 12-pt) it’s nearly always a take. If it’s the 1-pt or 2-pt anchor, it’s nearly always a pass. The 3-pt anchor is very case-by-case, depending on the gaps in blue’s prime, the race, white’s home board, and other factors. That situation takes a bit of study to master.1

What are the reasons for these conditions? Leading the race by 14 pips is self-explanatory — you want sufficient protection against a joker of a roll like 66 or 55. It turns out that a race much closer than 14 pips isn’t good enough. Next, we want 4 or fewer checkers on the midpoint before doubling because we don’t have any market losers until we reach that moment. With 4 or fewer checkers, we could clear the midpoint in a single roll with a good double, and then our opponent will no longer take our double. With 5 checkers or more on the midpoint, it doesn’t hurt to wait for a roll or 2 to see what happens — we might be happy we waited if our opponent rolls a huge doublet! Finally, if the opponent has a third checker on a different point in the homeboard (say, on the 24-pt, acting as a goalkeeper) it becomes substantially harder to bring all of our checkers home safely. Therefore, we need to be leading by way more pips in the race before doubling (say, 35 pips) to counter this advantage.

Could it really be this easy? Is it really always a take if you hold the 4-, 5- or 7-pt anchor? As mentioned, this is a gross oversimplification, and so you will find many exceptions… but you will be surprised how universal these rules of thumb seem to be. Take, for example, the following position where Gary was forced to move his own midpoint, he hasn’t built a strong prime to contain a turn-around shot on his side of the board, and he even has 2 blots in his homeboard:

This monstrosity of a position is still a take for Gary! The chance to land a shot on one of your midpoint checkers and to contain it is sufficient for him to cobble together a take.

Further reading:
  • A lecture by GM Zdenek Ziska on cubing, where he discusses holding games beginning at 29:22.
  • A video by GM Marc Olsen where he reviews many holding game blunders, where he also discusses the cubing rules above.
  1. This stark difference in cubing decisions between holding the 4- and 5-pt anchors and the 1- and 2-pt anchors make up part of the reason why it’s so important to fight for a good anchor in the early game. ↩︎

Next lesson: Doubling in bear-off racing conditions (intro to iSight)


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