Any reordering may decrease speed. "Strong" optimization need internal game information about using its files, that not accessible for defragmentator. Or very long information collect phase before optimization.
Today Add/MakeGap have two strategios Simple form moved out all files from Gap Area Form with DoNotVacate stay all files where thay is. I propose do not vacate this area immediatelly, but after next FileSelect return to this area and move out all file currently not selected (and not yet procesed of course)