Thrusty:
The point Sam was making was the same one I made in this article: https://uphillathlete.com/the-weakened-weekend-warrior/
Consistency and progression are two of the most important components of successful training. Randomly overdoing it on the weekends and then doing next to nothing all week due to work or fatigue is not the path to optimal results.
The ratios we used in the book are meant to keep you aimed in this direction.
Scott