I am not going to name the casino here, but it is in the Seattle area..... The game is Players Edge 21 - which is basically Spanish 21 (which is a variation of Blackjack). Here is a brief summary....
* In Spanish 21, the tens are removed from the deck, which is the one big advantage the house has over the player that is not present in Blackjack.
* The advantages the player has are: player blackjack beats dealer blackjack; player 21 always wins, blackjack players 3:2, there are several ways to get 21 that have 3:2, 2:1, and 3:1 payouts, player may split any two matched cards - up to three times, making four hands, player may double at any time, player may double a doubled bet.
The rule issue is this: in Players Edge 21, players are either permitted to double-double-double or "double for less," but not both. This casino allows both, which is huge. Consider: You are dealt a hard "5" against a dealer "6" up card. Basic strategy calls for a double.. You double and draw a "7." You now have "12" and about a 42% chance of winning the hand. Basic strategy calls for for you to stay as a second double will only raise you chance of winning the hand to about 48%, an increase that does not warrant doubling your bet.. However, "doubling for less" allows you to ante up one more dollar (even if you are at a $10 table!) for one more card. You can now increase your chance of winning the hand by six percent for almost nothing. In a nutshell, you can "double for less" any time a "double" or "double-double" draws a stinker of a card. In most cases is it superior to surrendering or staying.
As written, the rules should have a .4% house edge (assuming the side wagers are NOT played) - which is very low (a good game for the player). Add in that:
* The casino uses a "shoe" instead a an automatic shuffler. This creates volatility in the deck, where it will run high and low through play. Because more low cards can come out on a given hand, the shoe is more likely to run high, an advantage to the player (even if s/he is not counting cards).
* The casino allows you do double up to three times on a hand (typical is two). This allows the player to double very aggressively when the dealer's up card is a four, five, or six. That third double doesn't happen vary often, but can make for a huge hand with the player most likely to win.
* The casino allows the double-for-less, which allows you to have a shot a saving a failed double. (or double-double!) instead of surrendering.
I can only estimate the player advantage of these rules as the math is very messy and generally done with a computer program that simulates millions of hands. There does not seem to be any research online about the effect of these rules as such beneficial rules simply do not happen. Moreover, the "double for less" option has a different effect on the house edge, depending on your initial bet (if your initial wager is $100, the "double for less" is only 1% of your original bet, whereas if your initial bet is $3, the "double for less is 33% of your initial bet, which will have a dramatic change in your expected returns as a percentage of your total bet. Generally, computations for the house edge have nothing to do with the level of your wager. This is a different beast.)
Note: A huge player advantage, does not guarantee a winning evening. It is still gambling.
* A player not willing to really learn basic strategy (when to hit, double, stay, surrender based on his/her cards and the dealer's cards) will always play with a large disadvantage.
* I don't like to risk more than $100. On eight straight trips of about three hours each, I came out ahead. Twice, I left ahead by less than $15. Once, I was at $260. Once I was at $400. Each other time, I was between $150 and $200. However, this morning, I lost my $100.
* I still prefer to do casinos as shops as I don't have to risk any money and can come out with a good chunk of money.
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