For example- you wager $60,000 in Blackjack. You return $60,000 in Blackjack so you breakeven. $30,000 in wagers lost. $30,000 in wagers won. Those $30,000 in winning wagers were doubled. Now you've won $30,000 on $60,000 in wagers. If they weren't doubled you would be breakeven. So again-you would NOT have still been profitable $15,000 if a glitch doubled your winnings.