If you are NOT primary maintainer of the code, then you touch as little as possible to do what needs done.

Either way, touching code that is currently working just to touch it is a damn good way to break something. Since you didn't write it and aren't aware of all the contexts involved, you will probably break something important and not be aware that it's broken. In other words, don't do that. It will hurt. A lot. Like no-salary hurt.