I imagine the likely conclusion of it would come up with would be something like “decrease the size of the human population”.

If you commit the file on the secondary drive then it will be in the same repository as the rest of the code so you will end up with a large tree in that repo or you will need to move it over with the rest of the files. Why not make a symlink on the secondary drive pointing to the config in the repository? This way you can track it in git and have it located on the secondary.