Gambling novices might not notice the continuous shuffle machines sitting next to the green felt at three dozen Horseshoe Casino Baltimore blackjack tables. They are about the size of a small printer and make a barely audible clicking noise.
But serious players have taken heed. Anything that might tilt the balance between dealers and players in such a popular casino card game is considered significant in the industry.
In recent months, Horseshoe — joining many other casinos around the country — has introduced increasing numbers of continuous shuffle machines. By eliminating shuffling down time, the machines increase hands per hour by 20 percent or more. While some players say they prefer that quicker pace, the machines ultimately favor casinos' bottom lines by magnifying their slight statistical advantage.
They also make card counting impossible. The practice is employed successfully by a small minority of players, who try to calculate when favorable cards may be due and bet accordingly.
"Continuous shuffling machines are becoming more prevalent," said Stanford Wong, a gambling strategist and author. "I'd rather not see them being used, but I accept them as being a legitimate casino countermeasure. I'm hoping that good casino customers avoid continuous shufflers. But if customers are willing to gamble large enough when those machines are being used, then the machines are here to stay."
Horseshoe said it now uses continuous shuffle machines at 36 of its 83 blackjack tables, meaning customers can choose whether or not to play with the machines.
"It's been around since before I got in the industry more than a decade ago," Horseshoe's general manager, Erin Chamberlin, said. "It just helps improve the speed of play."
At Horseshoe and many other casinos, continuous shufflers typically are used at low-limit tables — those where the minimum bets are $25 or less. They are not used in Horseshoe's high-limit room, in which minimum bets are typically $50 or $100.
"It's fairly typical to feature those machines outside of high-limit," Chamberlin said. "High-limit players tend to be a little bit more traditional."
Maryland Live, the state's largest casino, also uses continuous shufflers.
"The players seem to like them because there is no down time for shuffling or changing decks out — [it's] continuous play," the casino said in an emailed response to a Baltimore Sun query.
Before being used, the machines are tested by independent laboratories commissioned by state regulators and by gaming control staff in the field.
On Monday, Horseshoe was using machines manufactured by Bally Technologies of Las Vegas.
"From a security standpoint, the shuffler eliminates card counting and shuffle tracking, and ultimately helps reduce losses due to cheating," according to Bally's website.
The machines hold six decks. After a few hands, cards that have been played are reloaded by the dealer into the shuffler, which randomly integrates them with other cards. That ongoing shuffling — and mixing of discards with unplayed cards — eliminates card counting, which can otherwise offer a way for practiced players to come out ahead over time.
In blackjack, a player draws cards against a dealer, trying to get closer to 21 without going over. A player applying basic strategy can reduce the house advantage to less than 1 percent. But players who count cards — keeping track of which cards have been played, and increasing their bets when there is an abundance of undealt 10s, face cards and aces — can turn the odds slightly in their favor.
In the absence of a continuous shuffler, cards are shuffled only after a "cut" card is reached signifying a "shoe" full of cards is complete.
With continuous shufflers, there is no way to predict which cards remain to be dealt.
"The reason blackjack became the most popular casino game was because it could be beat," said Colin Jones of the website BlackjackApprenticeship.com. "If the game becomes unbeatable, it kind of takes the allure away."
But Jones said continuous shufflers likely won't take over the game because casinos know that some players don't like them. Also, he said, "most legitimate card counters go to the high-limit room" where the machines are uncommon.
Horseshoe said it has long used continuous shufflers. It has increased their use as it added additional tables and moved others around based on players' preferences.
"We took advantage of reconfiguring tables and we put in the new machinery," Chamberlin said. "It was just kind of an evolution."
Chamberlin said card counting did not drive the casino's decision..
"There are so few card counters, quite frankly," she said. "That's not our No. 1 priority that we're looking at from that perspective. That's not what keeps me up at night. It's making sure that for the vast majority of customers we're providing them the game they want."