The little book that still beats the market

This book is targets people that don't really want to know the details, but only what to do. Because of that, it's explanations are simplistic and addresses more emotional concerns than analytical criticisms.

The fundamental ideas underlying the formula is reasonable: drawing from Benjamin Graham's Value Investing ideas. I don't think it's a matter of will is be profitable in the long run or not, but how much that compares to the market (eg S&P500). He did note how difficult it was to get historical data, and doesn't talk about overfitting or going beyond just back testing performance that he references all the time.

The author dismisses a lot of the criticism of the formula without supporting evidence. Only claiming that - less people will believe it and therefore it will continue to work. Which isn't a compelling argument.