I remember Doyle saying he had to change up his game after he published the book because to many people then knew how he played. But his game in the 21st century was not antiquated by any means. On High Stakes Poker thru 6 seasons he placed 3rd out of 70 of the biggest names in poker for money won. You'll be surprised at the big names on the bottom of the list. Negreanu was the biggest loser dumping over 2 mill on HSP:

https://www.reddit.com/r/poker/comme...d_on_the_high/