How to configure Finder to let me rename dotfiles? I always have hidden files set to 'visible' in Finder, because I'm a developer and I work with a lot of dotfiles.

But even with this setting, Finder won't let me rename a file beginning with a dot. It also won't let me modify these files by pasting over them etc; it gives an error like "The item “.gitignore” can’t be replaced because it’s invisible." Well, it's not invisible, I can see it, and I want to replace it, and it's mine.

I know how to use mv. I am asking about doing this with Finder.
I do not know what version of OS X you're using however I have no problem renaming dotfiles in Finder under OS X 10.8.5. That said, If your using a version of OS X that will not allow you to rename dotfiles in Finder and you do not want to use Terminal and the mv command, then a GUI option you can consider using is muCommander.