Cube Handling

Six Reasons Not to Double
Kit Woolsey, 1982

From Backgammon Times, Volume 2, Number 4, Fall 1982.

Most players when faced with a potential doubling position will simply mull the position over in their mind. Then if they like the position enough they will double; if not they will wait a roll. Too often this approach leads to a missed cube opportunity.

It is important to remember that a double is only an offer to raise the stakes. Obviously you should only consider raising the stakes when you are a favorite. Consequently, the first and most common reason not to double is:

1. You Aren't Winning

Keep in mind that being a favorite must take into consideration your opponent's ownership of the cube. For example, if you start with an opening 3-1 and he responds with a 5-2 you certainly are a favorite, but it is incorrect to double. If your opponent owns the cube, this more than compensates for your slight positional advantage: he will later be able to increase the stakes if his position becomes favorable; you no longer have that option.

Simply being the favorite may be sufficient justification to double, and it is always justification to consider doubling. A trivial example occurs when you have one man on the 5-point and one man on the 2-point in the bearoff, and your opponent has one man on the 1-point.
13 14 15 16 17 18 19 20 21 22 23 24
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Should Black double?
You are the favorite and there is no reason not to double, so go ahead and increase the stakes.

It is not always correct to double just because you are the favorite. However, it is necessary to find a reason not to double.

2. You Are Unlikely to Lose Your Market

This is the most common reason not to double as a favorite. What this means is that on most good-bad sequences (i.e., you roll a good number and your opponent rolls a bad number), he will still have a take. If this is the case, doubling is not necessary. You can have your cake and eat it too, for if things go well you can double next roll and he will still take, while if things go badly you will be happy not to have raised the stakes.

If a few market losers exist, the solidity of your position is an important consideration.
13 14 15 16 17 18 19 20 21 22 23 24
12 11 10 9 8 7 6 5 4 3 2 1
(From Backgammon with the Champions—Leibowitz vs. Corbett.)

Should Black double?

For example, in this position White certainly has a take now and will still have a take next roll on most sequences, but it is possible for Black to lose his market if he gets a lucky roll. Black's position is so solid that he should double just on the basis of these few market losers, since nothing bad can happen in the near future. However, if your position is shakey, doubling on just a few market losers may not be correct. Which brings us to the next reason.

3. Immediate Catastrophe Outweighs Market Losers

What this means is that, while you have market losers you won't lose your market by much, but if things go badly you will be very sorry you had doubled. For example, consider this position:
13 14 15 16 17 18 19 20 21 22 23 24
12 11 10 9 8 7 6 5 4 3 2 1
Should Black double?
Black has 24 hit numbers out of 36, and if he hits he will win about 80% of the time, which is sufficient to make him a favorite. In addition, a hit is a market loser since White would no longer have a take. However, it is correct for Black not to double. The reason is that when he hits he loses his market by only a little bit, but if he misses it is immediate loss of the game.

Reasons 2 and 3 are really tied in together. What it comes down to is that if you have a lasting advantage you need just a couple of market losing sequences to double, while if things can go bad quickly you may need a large number of market losing sequences. Once again, the amount by which you might lose your market is also important. If the good-bad sequences result in a close pass for your opponent, it may be correct to wait, but if they result in a clear pass you must double now.

4. Possession of the Cube Is Important

This is overrated by most players, but it can often be a consideration. If the market losing situation appears to make it close whether or not to double, cube ownership might swing the decision. Note that this only applies if you already own the cube, so your opponent doesn't have the option of doubling. If the cube is in the center he will have that option whether you double or not, so by refraining from doubling you still don't take the cube away from him. As an easy example, in a bearoff Black has one man on the 5-point and one man on the 2-point, White has 2 men on the 2-point.
13 14 15 16 17 18 19 20 21 22 23 24
12 11 10 9 8 7 6 5 4 3 2 1
Should Black redouble?
Black on roll is a clear favorite, and with the cube in the center a double would be clear-cut, but if Black already owns the cube it would be incorrect to redouble. White would have a strong redouble coming back if Black misses, and Black should not give him this opportunity. However, in most positions when you have sufficient market losers, ownership of the cube is not a major factor, so send it over.

5. You Are Playing for a Gammon

Here, you believe that your opponent has a pass if you double. You must reverse the procedure and look for "market gainers," i.e., examine the bad-good sequences. If you decide he will still have a pass after such a sequence you should always play for the gammon, but if he might, with some luck, fall into a take then you must weigh whether or not the gammon chances make the risk worthwhile.

6. Match Score Considerations

If you are ahead in the match and a double would put you out or almost out, it is often correct to hold back on a normal double. Your opponent may send the cube to a level where he can use all the points available, but you cannot. The classic case occurs when you have 2 points to go and your opponent has 4 points to go. At this score it is almost never correct to double in a complex position; you opponent, rather than needing 4 points to go at the Crawford game, will take, redouble, and play the game for the match. If your position is so strong that he still shouldn't take, then if the position is complex it is usually right to play for a gammon.

These are all the reasons why one might not double. The next time you are a favorite in a position, don't worry about whether or not your game is good enough to double. You already have a reason to double—you're winning! Instead, look for a reason not to double. If you can't find one, it is correct to double.

More articles by Kit Woolsey
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