Eight blackjack myths, corrected

Most blackjack folklore comes from remembering the hands that fitted a story and forgetting the ones that did not. The eight beliefs below are repeated at tables every day, and each one is contradicted either by simple arithmetic or by published analysis. Knowing why they are wrong makes you a calmer player and a better neighbour.

Myth 1: the player at third base controls the dealer’s hand

The claim is that the last player to act “takes the dealer’s card”, so a bad hit at third base costs everyone. The error is treating an unknown card as if it were known. Before the third-base player acts, the next card in the shoe is equally likely to be any remaining rank. If they hit, the dealer gets the card after it, which is also equally likely to be any remaining rank. Nothing about the dealer’s distribution of outcomes changes; only which physical card arrives.

Michael Shackleford tested this directly. In his blackjack Q&A he reports a simulation in which the first player’s expected return barely moved whether the second player used correct basic strategy or played terribly, and concludes that bad players are “just as likely to help you as hurt you”. The belief survives because a hit that bust the dealer is forgotten and a hit that saved the dealer is remembered.

Myth 2: never take the dealer’s bust card

This is the same myth from the other side: with the dealer showing a 6, a player with 16 is told to stand so as not to “take the bust card”. Basic strategy already says stand on hard 16 against a 6, but for the right reason. The dealer busts most often from a 5 or 6 upcard, and a player drawing to 16 busts on any 6 or higher, so standing has the higher expected value. The decision is about your hand’s probabilities, not about reserving a particular card for the dealer. With 16 against a 10, basic strategy says hit, and the table has no claim on your decision. See the dealer bust probability by upcard for the figures.

Myth 3: always assume the dealer has a ten

Tens, jacks, queens and kings make 16 of 52 cards, so a hole card is ten-valued 16 ÷ 52 ≈ 30.8% of the time. That is the most common single value but still less than one hand in three. Basic strategy is derived by averaging over all thirteen possible hole cards and every subsequent draw, which is why its decisions differ from the assume-a-ten shortcut.

Hard 12 against a dealer 2 is the standard counter-example. Assuming a ten gives the dealer 12 and suggests standing. Wizard of Odds’ infinite-deck expected value tables (dealer stands on soft 17) give an expected return of −0.2928 for standing and −0.2534 for hitting, so hitting is correct by about four pence per pound. The shortcut gets the play wrong because the other 69% of hole cards matter.

Myth 4: insurance protects a good hand

Insurance is a side bet, settled separately, that the dealer’s hole card is a ten. The player’s own cards do not enter the settlement. At a six-deck table with the dealer showing an ace and the player’s two cards ignored, 96 of the 311 unseen cards are tens, so a £1 insurance bet returns:

2 × (96 ÷ 311) − (215 ÷ 311) = (192 − 215) ÷ 311 = −23 ÷ 311 ≈ −7.4%.

Holding a 20 changes nothing in that sum. If anything, your two ten-value cards slightly reduce the share of tens left, making insurance marginally worse. Wizard of Odds’ multi-deck strategy is blunt: never take insurance or even money. The one exception is a card counter who knows the remaining shoe is unusually rich in tens; the full arithmetic is in insurance and even-money maths.

Myth 5: hot and cold dealers

A dealer who has drawn to 21 four hands running feels unbeatable, and players leave or move seats. The dealer makes no decisions; the rules fix every draw. Streaks of dealer wins occur at exactly the rate independent chance predicts, and a shoe does not know who is dealing it. Shackleford’s Q&A addresses a reader who tracked long dealer streaks and reports that any correlation between hands within a shoe is very slight and negative, concluding that switching tables “will not help”. Changing table after a run of losses is harmless, but it is a change of scenery, not of odds.

Myth 6: the table is due

The belief that a run of dealer wins makes a player win “due” is the gambler’s fallacy. Wikipedia’s article records its most expensive demonstration: at Monte Carlo on 18 August 1913 the roulette ball landed on black 26 times in succession, and players lost millions of francs betting ever larger sums on red because it was overdue. Each spin remained roughly even. In blackjack there is a narrow sense in which the past matters: cards dealt from a shoe are gone, so the composition of the remainder shifts. That effect is what card counting measures, and it is small, specific and unrelated to who won the last hand.

Myth 7: card counting is illegal

Counting cards in your head is legal. Wikipedia’s card counting article summarises the position: in the United States counting is lawful provided no device or outside person assists, Nevada courts have held it is not a crime, and it is not illegal under British law. In 1982 the New Jersey Supreme Court ruled in Uston v. Resorts International that Atlantic City casinos could not bar counters without a Casino Control Commission regulation.

What casinos can do in most places is refuse service, restrict a player to flat bets, shuffle early or ask them to leave. Using a concealed device or receiving signals from a confederate falls outside that protection and can be prosecuted. The practical consequences are covered in casino countermeasures and legality.

Myth 8: you need to be a genius to count

Films show counters as mathematical prodigies. The most widely used system, Hi-Lo, assigns +1 to cards 2 to 6, 0 to 7 to 9 and −1 to tens and aces, and keeps a running total. Dividing by the decks remaining gives the true count. That is the whole system. What is hard is doing it accurately at table speed for hours while betting correctly and not attracting attention, and the reward is modest. Wizard of Odds’ introduction to card counting puts a counter’s realistic edge under today’s rules at 0.5% to 1.5% and warns that it is “not as rewarding as television and the movies make it out to be”. Discipline, not genius, is the scarce skill; the Hi-Lo tutorial shows how ordinary players learn it.

Why the myths persist

Each belief gives a loss a cause: the stranger at third base, the cold dealer, the ten you should have assumed. Causes feel better than variance. The honest account is less comforting but more useful: under the site’s six-deck S17 profile, basic strategy fixes the best play for every hand, the house keeps a small edge, and short-run results scatter widely around that edge. Everything else is memory doing its selective work.

Related reading

• Basic strategy
• Insurance and even-money maths
• Casino countermeasures and legality
• Betting systems debunked