Omission, Commission, and Soft Doubles at Blackjack

1 March 2005

By Alan Krigman

Some so-called "soft" two-card blackjack hands, incorporating aces, offer players more "expected" profit by doubling down than by hitting or standing versus low dealer upcards. This is why the move is specified in those Basic Strategy charts. Doubling, if you're a neophyte, means matching your original bet with an auxiliary wager then drawing one and only one additional card.

The statistical differences between the optimal and next best options to manage the alternatives for these situations are not overwhelming. However, understanding and proficient handling of soft doubles does distinguish solid citizens praying for elusive good fortune from gamblers fearing occasional bad luck.

Basic Strategy for soft doubles is simpler than most individuals imagine. With the two lowest candidates, soft 13 or 14, double only against a dealer's five or six. With the two highest, soft 17 or 18, double against a three, four, five, or six. With the two in between, soft 15 or 16, double in between against a four, five, or six. That's it. No other soft totals. No other upcards.

Ordinarily, blackjack players would be well-advised to follow the dogma of Basic Strategy. It surely beats being struck by a bolt of lightning. An eventuality many believe befalls those who don't double when it's decreed. This would exemplify a sin of omission, which Ogden Nash (in "Portrait of the Artist as a Prematurely Old Man") described as "bad in the eyes of all right-thinking people, from Billy Sunday to Buddha,/ And it consists of not having done something you shudda." The faithful also dread disaster if anyone doubles when "the book" otherwise ordains. This would typify a sin of commission, which Nash pictured as "very important,/ And is what you are doing when you are doing something you ortant."

Casinos aren't ordinary places, though. So "ordinarily" doesn't always count. And breaking the rules may not be wholly unwise, depending on your personal preferences and the prevailing winds.

In particular, chances of winning ?? as opposed to expected profit ?? are slightly greater hitting soft 13 through 17 or standing on soft 18 than doubling. Say, for instance, you have soft 15 or 16 versus four-up, with so much at risk on the hand that you'd sweat adding what it takes to double. You might prefer the increased shot at winning less, to the elevated exposure you get by boosting expectation a bit, so you prudently hit.

Alternately, what if you were hell bent for leather or going for broke? Then, you might rationally accept small penalties in likelihood of winning and edge, opting to try for the extra profit by doubling on soft 18 with the dealer showing a deuce.

How much edge does an optimist sacrifice by consistently doubling into dealer twos, threes, and fours when the math is tilted toward hitting or standing? Assuming otherwise perfect Basic Strategy in games where players can resplit pairs, house advantage would rise from 0.44 to 0.49 percent with eight decks and from 0.42 to 0.47 percent with six ?? equivalent to five cents per $100 bet during the course of a session either way.

Were you a confirmed pessimist you probably shouldn't be gambling at all. In case you were, though, by standing on those soft 18s and hitting on the other recommended soft doubles, edge would creep up from 0.44 to 0.53 percent with eight decks and 0.42 to 0.51 percent with six. You'd be enriching the casinos nine cents more than they demand for every $100 you wagered.

As ever, you have to decide this for yourself, considering such subjective factors as your temperament and goals. If you do elect to flout the gurus, you can take solace n the fact that the worse the bosses think you play, the higher they'll rate you for comps. The poet laureate of the casinos, Sumner A Ingmark, bows to Ogden Nash to give you guidance in which direction to go:

No, you never get any fun
Out of things you haven't done.
But they are the things that I do not like to be amid,
Because the suitable things you didn't do give you a lot more trouble than the unsuitable things you did.
The moral is that it is probably better not to sin at all, but if some kind of sin you must be pursuing,
Well, remember to do it by doing rather than by not doing.