It is understandable that a user may not be aware of this fact, but the installation process for Rockbox itself is incredibly simple.
The complicated part of the installation on targets where we operate as a full firmware replacement is the bootloader, and generally speaking that process must only be done once, except for the very rare times when we push a change out that actually requires an updated bootloader.
Updating the Rockbox binary with Rockbox Utility isn't doing anything that you yourself couldn't do manually with relative ease should you desire to do so, but it does offer some handy aspects like automatic device mountpoint detection. All the Rockbox binary installation is doing is extracting an
archive to the root of the device, overwriting the original files, leaving system generated files (various configuration files for system and plugins) intact. No user generated files are touched.
[Saint]