No, you wouldn't. You'd just maintain the templates, and generate the "real" config files automatically.

Introducing Templates is effectively changing your problem from "read the config files, search and replace in them, and write them back" to "Fill the templates with variables, and write the output into the config files".

If that confuses you, your best bet is to stay with your original solution, and wait until somebody has a better suggestion on how to handle it ;-)