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Basic strategy says to double down on 11 against a dealer 10. However, many players chicken out and hit instead because they are afraid that the dealer might have a pat 20. Well, did you know that when the dealer has a ten upcard (and doesn't have a blackjack), he will wind up with a 20 roughly 33% of the time? Meanwhile, a player holding an 11 and taking one card (i.e., doubling down), has roughly a 31% chance of getting a 21 (by drawing a ten) and an 8% chance of making a 20 (by drawing a nine). In other words, you are considerably more likely to make a 20 or 21 with a one-card draw than the dealer is to make a 20. Moreover, think about this: if you draw a 7, 8, 9, or 10, and the dealer has the same card in the hole, you still win! Even though doubling lowers slightly your chances of winning (because if you draw a small card, you can't hit again to improve your total), your monetary gain is still greater by doubling because you bet twice as much money.

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If I told you that playing an 8 twice, against a dealer 10, loses less money than playing a 16 once, would you believe me? Probably not, but guess what, it's true. When you hit 16 against a dealer 10, you'll win only 23% of the time and lose 77%, meaning you'll win about four hands out of every 17. This is why holding a 16 against a 10 is the worst hand in blackjack. However, when your 16 is a pair of 8s, you have an out, namely splitting, because now your chances of winning when you start each hand with a single 8 against a 10 are 38%. In both cases (hitting and splitting), you are going to lose money, but it's still cheaper to win 38 hands and lose 62 on each 8 (by splitting) than to win 23 hands and lose 77 once (by hitting). Still not convinced? Here's the simple math to prove this point.

Hit: Bet $10 on the hand. Win 23 hands for a total win of $230. Lose 77 hands for a total loss of $770. After 100 hands, your net loss is $770 minus $230, or $540.

Split: Splitting 100 hands of 8s creates 200 hands, with each hand starting with an 8. If you bet $10 on each split 8, you'll win 76 hands (38% of 200), for a total win of $760. You'll lose 124 hands for a total loss of $1,240. Your net loss is $480. Therefore, losing $480 (by splitting) is, I'm sure you'll agree, better than losing $540 by hitting.

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It seems logical to split 9s when the dealer is showing a small card. However, it may not make sense to you to split 9s against a dealer 9, so you may stand with your "strong" 18. However, a hard 18 will beat a dealer's 9 only eight times out of twenty, while you'll win almost half the time with a 9 facing a dealer 9 (actually, you'll win 9.5 out of twenty hands). The bottom line is that even though you think an 18 is a strong hand, it isn't against a dealer 9. To get close to break-even on this hand, you need to be aggressive and split. (Note, also, that when resplitting and doubling after splitting are permitted, there is the extra attraction of being able to double your 11, as per our first example, should you draw a deuce to any of your 9s.)

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There is a "rule" in blackjack that says you should never risk busting your hand when the dealer shows a weak upcard. That may be true for most stiff hands but it's not the case when you are holding a 12 against a 3. When you think about it, there are only four cards that could bust your 12 - a ten, jack, queen, or king. On the other hand, five cards will get you to 17-21 (a five, six, seven, eight, or nine). Therefore, more cards will get you into the safe 17-21 zone than will break you. The other factor that works in your favor is the dealer's 3 upcard, which is not as weak as, say, a 4, 5, or 6 upcard (she will bust less with a 3 upcard compared to the 4, 5, or 6). The bottom line is that you will lose slightly less by hitting 12 against a 3 than by standing.

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Some casinos allow the surrender rule, and the correct basic strategy play for this hand is to surrender. Yet, many players will not surrender because they don't think it makes sense to give up half their bet without a fight. Let's look at the logic of surrendering. When you surrender a hand, you automatically lose 50% of your bet. Therefore, doesn't it make sense to surrender any hand when, for any other alternative, your chance of losing minus your chance of winning is greater than 50%? This happens to be the case with a hard 16 against a dealer 10. If you hit your 16 against a 10, you have a 23% chance of winning (pretty bad) and a whopping 77% chance of losing. That means your overall disadvantage is 54% (77% minus 23%). Now let me ask you this: would you rather lose 50% of a bet all the time, or nearly 54% of the same bet, on average? Either way you're a loser, but here's the kicker: when you surrender, you'll lose almost 4% less money in the long run than if you hit.

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My friend and fellow blackjack author Fred Renzey (Blackjack Bluebook II) has this to say about why you should always hit this hand: "If you play an entire lifetime of blackjack and are dealt a pat 18 on every single hand, you'd die a small loser! That's the grim truth. And that dealer's 9 up there doesn't exactly help your chances any. However, the ace in your hand gives you some flexibility. If you stand, you'll win eight times out of twenty. If you hit all the way to soft 19, a hard 17, or bust, you'll win nine out of twenty. So take your choice ... eight wins or nine wins."