Just wanted to point out that:

60:40 ratio of Protein to Fat

refers to ratio by WEIGHT, not by percentage of calories.

• 90:10 ground beef is 53% fat by calories
• 95:5 ground beef is 36% fat by calories
• a large egg is 64% fat by calories
• chicken breast with skin is 50% fat by calories
• lean beef sirloin, trimmed, is 55% fat by calories
• etc, etc

In his "NEW Diet Revolution" (1992), Atkins stated that the rich, cream- and butter-heavy recipes were intended for special occasions, and that "eating lean foods is quite appropriate" (p.336). However, I doubt the good doctor intended his diet should be primarily skinless chicken breast, fat-free cottage cheese, egg whites and water-pack tuna. Using the sample menus in both the 1972 and 1992 books, fat content averages 60% by calories.

His admonition against "high fat" refers to the Fat Fast, which he reserved as a temporary measure, only for those with extreme metabolic resistance who were unable to achieve ketosis by following the general rules of Induction. The fat fast is based on the work of Frederick Benoit, consisting of 1000 calories .. 90% fat (90g), 10% protein+carb (ideally 15g prot, 10g carb). As with everything in life, it ended up being used and abused by too many people who simply wanted to speed things along, and who distorted the proportions by eating too much protein and too many calories in the process.

Hope this is helpful