[dnanian]

OK, I've reworked page 10 of the manual a bit to -- hopefully -- improve the description. What do you all think? Is this clearer?

Copy newer and Copy different, the other two During Copy options, control what SuperDuper! does when it copies a file from a folder on the source volume to the destination, and finds there’s already a file in that location with the same name.
When Copy newer is selected, the file on the destination is replaced with the one from the source if the file on the source has a newer (more recent) modification date.

Copy different replaces the file on the destination if the source file is different (not necessarily newer) in date, size, HFS+ meta data, attributes, etc. So, the file on the destination is replaced if it’s not exactly the same as the source file.

In both cases, files on the destination that are not on the source are left as-is.