[hyperpape]

I never read more than a fraction of the first edition, but I found it valuable. The key idea was that refactoring was a methodical, careful process that consists of steadily taking the code from one working state to another. At the time, refactoring was a dirty word at my company, and people didn’t distinguish it from rewriting code in any arbitrary fashion.

[quietbritishjim]

This sounds mostly like the first chapter, which was the bit I enjoyed the most. That was about automated testing, and a whole book about that might've been quite useful.

[hyperpape]

Automated testing is great, but you can apply the core idea to code without automated tests. The difference is that you have to be even more mechanical and cautious.

In addition to the principles about refactoring, reading a few of the examples helped to drive in how methodical it was.