When I'm copying file that already exists, Dolphin opens up the "File Already Exists" dialog and tells me if there's a difference between two files. If it determines the files are identical, it shows the "The files seem identical" information. When copying multiple files, it does the same thing for each and every file. The "Skip" and "Apply to All" options, when used together gives me the option to skip all existing files. An additional nice feature would be "Skip if the files seem identical" that can be used with "Apply to All". Currently, when copying multiple files, I've to manually check if Dolphin determined the files seem identical then press skip. Since this isn't a bug report, rather a feature request, I didn't include the parts related to bugs (like steps to reproduce, etc).
I totally agree with this enhancement. If your copying procedure is interrupted for some reason eg. hanging, power loss etc., then copying procedure is leaving behind half-copied files. In such cases, when you press "skip", these files will not be overwritten. Therefore, another option must exists that will tell "skip only identical" and overwrite not identical files. Also, if you have 1000+ files, "skip identical" and thus "visually checking" only those files that differ or missing in the visual aid of dolphin copy procedure, will be very helpful improvement. I must press "skip" multiple times with danger to skip non identical files. This is not very convenient.