The difference between a person who can play poker and a person who can win at poker has very little to do with the way they play cards. The expert player, and even the advanced beginner, realizes that they have to play their opponents to know when someone is betting heavily because they have a strong hand, and when they are bluffing. If you can read your opponents well enough to know the difference, you'll fleece them every time. This same technique can be used in blackjack—not for every hand, but for enough of them to make a significant difference.
The "Tell"
The basic technique to knowing what's in your opponent's hand is paying close attention to their mannerisms and recognizing patterns of behavior, called "tells", that they exhibit when they have a high hand, and others they exhibit when they have a low one. By recognizing tells, a poker player can be reasonably certain when an opponent has a high hand and when he is bluffing.
The existence of tells is no myth. Psychologists have done a great deal of research into the mannerisms of honest and deceitful people. Their findings indicate that most people have an aversion to lying, and this aversion manifests itself physically through obvious and predictable mannerisms. At the poker table, a player may smile when he is bluffing—and once you recognize that, you can call his bluff every time.
On the other hand, a person who is trying to hide the fact that they are lying will try to mask those mannerisms in a way that is no less obvious or predictable. A person who knows that people smile when they lie might smile when he has a strong hand to trick his opponents into staying in the game. However, if you observe this person closely over the course of several hands, you'll be able to recognize exactly what his smile indicates, and know to fold when you see it.
Another difficult in reading tells is that each person manifests them differently. Some people smile when they bluff. Some may become more stone-faced. Some may fidget with their cheques. Some may scratch or pick their noses or fiddle with their wristwatches. In order to use a tell, you must be observant of each person's individual mannerisms, and make the connection between those mannerisms and the outcome of each hand.
All things considered, reading tells is difficult—but well worth the effort.
Using Tells in Blackjack
Moving from the poker room to the blackjack pits, tells can still be useful. If you can read the dealer's tells, you can determine when the dealer has a high or low hole card—a bust or pat hand—and play your own hand accordingly.
In most casinos, the dealer does not look at his hole card until all players have completed their hands, so "tells" aren't useful at all. However, if the dealer is showing an ace or a ten-value card, he must check his hole card to determine whether he has blackjack before play commences. This will happen in five out of thirteen hands—38.5% of the time—which is enough to make a significant difference in your winnings.
Exploiting the Tell
When the dealer checks his hole card, he knows the value of his hand—and his tell will manifest itself. Be very observant to notice anything peculiar, however subtle, in the dealer's mannerisms. Watch his expression, where his eyes tend to rest, where he places his hands. Be attuned to minor changes in his expression, demeanor, or the tone of his voice. See if he breathes differently, sweats, or fidgets.
If the dealer's tell isn't obvious, you can often draw it out by hesitating over your decision whether to hit or stand, surrender or stay in the game. In addition to an aversion to lying, there is also a psychological tendency for compassion (or, if tour dealer hates you, cruelty) that will manifest itself physically. A tell may manifest itself while you're agonizing over your decision or you've announced your move.
After establishing a mental inventory of the dealer's behavior, demeanor, posture, mannerisms, and so on, wait until the end of the round. Note whether the hole card was low (two through five, six if the upcard is a ten) or high (seven through ten, ace if the upcard is an ace). It may take some time to put the two together, but eventually, a pattern will unveil itself.
If it's not obvious how the dealer's tell can be exploited, consider this: if you're holding fifteen or sixteen and the dealer's upcard is a ten, basic strategy tells you to surrender. If you're reading the dealer's tell, and are confident he has a bust hand, the smart move is to stand pat and collect your winnings when he breaks. Also, it would be worthwhile to double that ten or eleven, perhaps even a nine or eight, even though basic strategy says merely to hit against a ten and/or ace.
Don't Be Stupid
Here's something that should go without saying, but probably needs to be said: never let the dealer know that you have recognized his tell, or he will immediately try to control and conceal it. Don't mention it to the dealer, don't mention it to another player, and certainly don't mention it within earshot of the pit boss.
The least unfortunate consequence is that you'll lose your advantage. The most unfortunate is that you and the dealer could both end up in prison for conspiracy to defraud the casino. Reading tells isn't a crime, but working out a signaling system with the dealer certainly is—and while the burden of proof is on the prosecution's side, any communication or admission on your part is damning evidence.
Aside of blabbing about it, you may give off tells of your own—unconscious signals that you've noticed the dealer's tell. Remember: while you're looking at the dealer, he's looking right back at you (and so are the pit boss and camera crew). The dealer will control or conceal his tell if he knows you've spotted it, and the pit boss will certainly switch dealers if he suspects anything, eliminating your advantage.
Common Dealer Tells
Tells vary from person to person, so there's no reliable list of specific mannerisms to watch for. The following list shows some of the predictable tells, but they should be considered as examples only, and not to be substituted for close observation of your individual dealer.
A dealer who is "with the players" (because winners tip) will be pleased to have a bust hand. He might smile or seem more cheerful or at ease when he sees a low card under that ten, or the opposite if the hole card is high.
A dealer who is "against the players" (because raises and promotions go to dealers who earn—or because you're obnoxious and loathsome) will have the opposite reactions to a low or high card.
If the dealer checks the hole card twice, it could be a sign that the hole card is high. The difference between a numeral and a letter is more immediately noticeable, but if the dealer checks quickly and sees only a letter, he may need to look again to see if the letter he saw was a "K" or an "A."
When the dealer has finished checking the hole card, placing his cards slightly to his right could be a sign that he has a low hole card (and will need to hit it). Placing them squarely in the center could mean that he has a pat hand (and won't need room to lay hits).
It bears repeating that these examples all use terms such as "could" and "might" because they are examples of possible tells, and certainly not universal truths.
Casino Defenses
A sharp pit boss will know all about this business of reading tells and train his dealers against it, and veteran dealers are largely jaded against empathy with the players. Even the most cautious individuals will have tells, however, though if they are indifferent to the outcome or are conscious of their own behavior, the tells will be harder to spot.
The most common defense against the player who can read tells is changing dealers. When a fresh dealer comes to the table, you'll need to start over, observing his mannerisms and the outcome of hands, until you can identify the tell. It's worth noting that dealer rotations were designed to make it inconvenient for a dealer to knowingly conspire with a player, so it will look suspicious if you seek out the same dealer or follow him about the pits.
A more effective defense has been put in place at some casinos: a remote recognition system is used to read the cards. The dealer slides the cards over a scanner, presses a button for ten or ace, and is told only if he should turn or deal. At these tables, reading tells is useless, as the dealer has no knowledge of the value of the hole card until it's overturned.
Source: www.ace-ten.com
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