The project manager must be the direction of real-time control of the project because most of the projects are not out of control suddenly happen, but slowly, immutable completely out of control. Characteristics of the system may be a characteristic of a deviation from the norm, a little bit of delay in the project schedule. In this case, if an individual or as a manager should not tolerate the violation of norms, we must look at yourself every day, look at the team, and promptly correct the problem, correct the direction of the team.
The book is a principle to implement DRY (Do not Repeat Yourself) principle, which is every good developer must follow the specification, the encoding process anywhere Do not repeat, repeat temporary because the time saved will give future maintenance and use huge trouble if there are duplicate code is found in violation of the principle of orthogonality or other places to look for opportunities to reconstruct immediately. So that it can have a faster, better, more robust code.
Another brings me deep feelings are warm boiled frog story, let us not be taken lightly.