Yeah, doing it via the "save core remap file" just means that the actual remap itself is saved to its own file in its own folder. So if you cock up and save a core override that breaks the system (shader incompatibility, a graphics option your PC doesnt support) you can delete the override without losing your controller mappings, also you can just copy the remaps to other builds without having to use the exact same override, as the other PC may need different settings..