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Better Preempts: What is the upside? part I
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Earlier articles focused largely on self-protection--how to preempt without risking painful consequences.However, controlling damage is only half the battle. The other half is finding opportunities where a preemptis likely to generate a big reward. This is the first of several articles on judging whether an auction offers a small or a large reward for preemption and adjusting your preemption tactics accordingly.

Large and Small Rewards

Experts think of a preempt like a bet. With X% chance of winning, they are risking $Y to gain $Z.An expert would rather risk $10 for a chance to win $100 than for a chance at $1. An expert would also prefer his bet has a 75% chance of winning rather than a 10% chance of winning.

To change from the betting metaphor to preemptive terms, we would much rather risk -500 in a doubled preempt for a chance to win +500 than for a chance to win +50.We have encountered two scenarios where reward for preemption is low:

  • The hand belongs to us. In this case a preempt can't win anything at all. If we bid slowly instead, we would reach the same or a superior contract as we would if we preempt.*
  • The opponents can only make apartscore.

If you were certain the opponents could only make a partscore, or that the deal belonged to your side, you'd never risk a large number on a preempt, since the rewardfor victory is small. In practice nothing is ever certain, but often your hand and the auction suggest that the deal belongs to you, or that the opponents probably cannot make a game. In those situations your preemptive strategy should be conservative to protect yourself from numbers.

Fortunately, in most auctions,there is some chance of winning big with an effective preempt. Buteven when a bet offers a large reward, experts will not automatically place a large bet. Suppose the bet will win only 1 time in 10. The expert would only be willing to risk $1 to win$10 if the chance of success is 10%. In preemptive terms, if we are going to risk going -500 or -800 we would rather do it with a good chance to collect a 500+ reward than with a poor one. And if we think the chances are poor we should preemptconservatively, only risking -100 or -200 for a small chanceto win +500.

How can you tell when preemption will or will notsucceed frequently? Let's look at two examples. We will start with anauction where a preempt is unlikely to succeed.

___________________
* The exception is opening game bids. An opening 4M or a 1m -- (P) -- 4M response can be bid with a weak or a goodish hand. When bid on a good hand, you hope 4M shuts the opponents out of a cheap sacrifice. You intentionally risk missing a slam in exchange for a better chance to avoid an opposing sacrifice. If you don't fear a sacrifice, or you think slam chances are too good, you bid slowly instead.

Auction 1

W
N
E
S
1
P
2
3
?

Consider the three ways a preempt can win and whether these outcomes are likely in the above auction:

1. A preempt might drive the opponents into the wrong strain.Having already found a fit, the opponents will rarely get to the wrong strain after your 3 bid. They could defend when they should declare, but they would virtually never play game in the wrong strain.

2. A preempt might drive opponents too high or too low.With RHO a limited hand, LHO often already knows whether the deal belongs inpartscoreor game, and with RHO so weak, slam isalmostalways not a factor. Your preempt can only give LHOa problem when he has invitational values, and even then, he will make the right decision at least half of the time.

3. A preempt can locate a cheap sacrifice.
This is the best chance for your preempt topick up a decent number of IMPs, as longas partner can judge accurately to avoid a phantom sacrifice.

Why was this auction so poor for preemption? The boat had already sailed before it was your turn to bid. With their 1 -- 2 sequence, the opponents hadfound their fit, and one player had limited his hand. Consequently,therewas little uncertainty remaining about the deal, and the chance a preempt would cause them to err was small.
Does this mean you should never preempt after a raise? No. You don't want to miss the occasional cheap sacrifice. However, it does mean you don't want to risk a big number after a single raise.Let's take a look at some hands in this auction.
South
KJxxxxx
xx
Qxx
x
W
N
E
S
1
P
2
?
Holding this hand you should pass. 3 risks a large number with little upside.
South
KQJxxxx
x
A10xx
x
W
N
E
S
1
P
2
?
This is the hand a preempt shows when preemptive tactics are oriented towards finding a sacrifice. Although you might be tempted to bid 4 directly, how wouldyou feel if partner tabled QJTx of hearts and a stiff spade? You would have just traded a plus score versus 4 for -300 when 4 was doubled. Preempting 3 allows your side to save when partner has limited defense, and protects you from a phantom sacrifice when he does.
How should advancer continue after your 3 preempt? If you promise a very good preempt, partner can afford to sacrifice often and with relatively dull hands. He can judge accurately when their contract will be cold, and he doesn't need much to bid further since he knows your call showsexcellent offense. Your preempt is a strong invitation to sacrifice.Let's look at this from the point of view of the advancer:
North
A10x
Jxx
xxx
Kxxx
W
N
E
S
1
P
2
3
4
?
This is an easy 4 bid. Your hand is rather poor, so what makes it a clear 4 call? First, you can tell that 4 is a big favorite to make, since partner's hand must be offensively oriented and you have little defense. Second, given the 7-8 offensive trick hand your partner has promised, you can more or less guarantee 8 tricks for your side, and possibly 9. So a sacrifice is likely to be profitable.

Auction 2
The last auction was no fun. Who likes to hear that our wild "creative" calls are pointless? Perhaps we need to look at a high-success auction as an antidote.
W
N
E
S
1
3
?

This time every factor favors preemption: The opening call means the hand likely belongs to the opponents, and at the same time, opener's hand is wildly undefined. He might hold a 4-3-3-3 12-count or he could hold a distributional 7-4-1-1 19-count. Responder has no idea if they have a fit and if they do, where their fit lies. Furthermore, responder has no idea whether thehand belongs in partscore, game or slam, since he has no idea yet how strong opener is. Since your call consumed so much bidding room, the opponents will often be stuck with a pure guess.
Chances that this preempt drives the opponents into the wrong strain or tothe wrong level are high. Your preempt also allows to find a cheap sacrifice whenadvancer has a fit and little defense. The opponents will have more trouble judging when to defend against this 3 than the last one, because they are uncertain of the correct level. They fear collecting a paltry +500 when they were due a slam bonus.
What does that suggest about preemption tactics? With such good chances, preempt as often as possible. The only way to preempt more often is to preempt on a wider range of hand types, including many on which risk is substantial or the hand includes significant side defense.
Given the large upside to preemption, 3 is a reasonable call with each sample hand below:
South
KQJ98x
x
xxx
xxx
W
N
E
S
1
?
South
KJ9xxx
xx
AQ10x
x
W
N
E
S
1
?
South
KQJxxxx
xx
Qx
xx
W
N
E
S
1
?
South
QJ9xxx
x
x
xxxxx
W
N
E
S
1
?
South
QJ9xxxx
Axx
x
xx
W
N
E
S
1
?
What about poor partner? If you preempt on such a wide range of hands, won't he have a terrible time judging what to do? Yes he will. In general, he must guess that your 3 call was already an overbid, and err in favor of conservatism, since you are far more likely to have stretched than to have been dealt a conventional preempt. As a result, he may miss a cheap sacrifice a small percentage of the time when your preempt had full preemptive values. That sounds bad, but remember you are preempting five times as often as the guy who preempts only with full values. As a result, your many victories will outweigh the occasional missed sacrifice. In favorable preemption scenarios, this is a cost of business.
Looking again from the point of view of advancer:
North
A10x
Jxx
xxx
Kxxx
W
N
E
S
1
3
X
?
You have the same hand we saw before, but this time you wouldn't dream of bidding on. 4 might either go for a huge number or it might be a phantom sacrifice. You have no way to tell because your partner's 3 call is so wide-ranging. Fortunately, it doesn't matter much in the long run. You will win plenty of boards when the opponents have bid too little/too much, or arrived at the wrong strain because partner's preempt consumed so much bidding space. Passing will lead to success more often than not. In this scenario, the prempt was oriented towards making the opponents guess wrong, not towards finding sacrifices. Sacrifice only when you have a big fitand shape and limited defense.
Conclusion
Experts preempt aggressively only in situations where they believe that the reward is large and chances of success are high. In these situations, they are willing topreempt on hands where losses could be high if opponents have the cards to double them.
The upside for preemption varies enormously based on the preceding auction. The upside for preemption is low whenever any of the following are true:
  1. The handbelongs to you
  2. The opponents can't make a game because you have significant defense
  3. The opponents probably already know their best final contract
Whenever upside is limited, employ solid preempts and be conservative in advancing to protect yourself from numbers, and to allow your partner to judge accurately when to sacrifice.
The upside for preempting is high when:
  1. The hand belongs to them
  2. The opponents can probablymake a game
  3. The opponents don't yet know the correct strain or level
When the upside is good, be aggressive, bordering on foolish, to collect the frequent large rewards for preempting.
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