Dahl's whole system is based on the idea that, when you win a hand, you should let some of the winnings ride on your following bet. He says he's found that "luck runs in streaks." Of course that's nonsense. Any thoughtful person should realize that winning one hand of blackjack makes you no more or less likely to win the next. What's more, the whole system is explained in about three pages, and the rest of the book is fluff. If you play blackjack and don't want to count cards, make up your own progression system and have a good time. You'll do just as well without reading this worthless little book. Incidentally, I've just finished reading The World's Greatest Blackjack Book by Lance Humble. It's very insightful and pleasant to read. I recommend it highly for anyone who would like to broaden his knowledge of the game