Comment by markus_zhang

Maybe there is no such thing as clean code by following a set of rules. I know the author of the book never advocateshis book as a "bible" but it does give the reader such feeling.

There is only years, decades of deep experience into certain domains (e.g. game rendering engine programming, or, Customer Relationship backends), extra hours reading proved high quality code, countless times of reflection on existing code (that also means extra hours reviewing existing code) based on the reading and a strong will to improve them, not based on some set of rules, but based on common sense on programming and many trials of re-writing the code into another form.

I think ultimately it goes down to something similar to 10,000-hour rule: We need to put down a lot of time in X, and not only that, we also need to challenge ourselves for every step.