From the perspective of those of us on the outside of the table felt, there's nothing more dreaded in blackjack than a dealer with an ace showing. About 30 percent of the time, the scenario results in dealer blackjack. In other words, it's bad news.
Most casinos around Northern California offer two basic options for players in this scenario. The first applies to all players at the table: the opportunity to "insure" your hand against a dealer blackjack. The second applies only to players who have received blackjack themselves: the option to take "even money," or a 1:1 payout, instead of what the table normally pays for 21. Both of these moves are a waste of time and money.
Let's start with "insurance." In the name of the Geico gecko, this wager really isn't "insurance" at all; instead it's a side bet that allows you to wager half your ante that the dealer has blackjack. If he does, you win at 2:1 odds. If he doesn't, you lose the insurance bet.
Considering the frequency with which dealers showing aces score blackjack, this might seem like a shrewd move. True odds suggest otherwise, and they differ depending on how many 10s you have in your hand. In fact, 19s and 20s, which novice players perceive to be the best hands to insure, offer some of the worst odds of all.
(Without dropping too many numbers on you, in order to justify insuring a 20 with a $10 bet, you'd need to get paid $25 to make the move worthwhile.)
If you think this is akin to throwing away cash, accepting "even money" when you have blackjack (and the dealer has an ace showing) is even worse. Normally, player blackjacks pay 3:2 or 6:5, depending on the table and the casino. But by accepting even money to avoid a push, you're hedging your bets into a payout of 1:1.
Let's get real: Taking even money against a dealer ace guarantees you some profit in a situation where there is relative likelihood you'll push. Still, that guaranteed profit comes at a price, and at a 3:2 table, the price is roughly one-third of the money you should get paid. Put differently: Wouldn't you rather win $15 on a $10 bet, instead of just settling for $10?
The only time accepting even money might be wise is if you're counting cards and you have strong reason to believe that more than one-third of the cards left in the deck or shoe are 10s.
My personal take: Steer clear of both options under almost all circumstances. Unless a payout matches true odds, don't bother with it at all. Yes, this strategy results in pushing (and therefore not winning) with a blackjack every once in a while. In the long run, however, as the numbers show, this is the play that will make you more cash.
Matt Villano is a freelance writer. E-mail: 96hours@sfchronicle.com Twitter: @mattvillano