There's no silver bullet. My opinion is that you should weight alternatives without repetition and with repetition and choose the most appropriate one. Also if in the future you feel that this common code is becoming more complex with options and switches, feel free to remove it by inlining, either completely or in a few places. Often it'll allow for better code or it'll allow to find out another way to extract common code.
Basically I like the refactoring approach. You have a set of refactorings. Like extract method / inline method. The point is that every refactoring is two-way. And both ways are useful in different situations.
To support this approach, sane IDE is a must and strictly typed language is preferable You should refactor your code without fear of breaking unrelated code.
What I definitely think is overrated is "if it works - don't touch it" principle. It's lazy and in the end it creates much more work than if one would gradually improve something that works.
Basically I like the refactoring approach. You have a set of refactorings. Like extract method / inline method. The point is that every refactoring is two-way. And both ways are useful in different situations.
To support this approach, sane IDE is a must and strictly typed language is preferable You should refactor your code without fear of breaking unrelated code.
What I definitely think is overrated is "if it works - don't touch it" principle. It's lazy and in the end it creates much more work than if one would gradually improve something that works.