For me the naming scheme has been great when I’m mastering a single song for somebody and might have a folder with 2 or 3 versions of the same song (just different formats). Since you can’t have the same file name twice in a folder, now I can tell WaveLab to _1644 to the end of the 16-bit/44.1k WAV version and then tell WaveLab to add _2496 to the end of the 24-bit/96k WAV version, and of course this doesn’t end up in the metadata of the file, just the file name.
Also useful for adding _SIDE_A or _SIDE_B etc. for vinyl and cassette pre-masters where the file needs to be one file per side rather than each song as it’s own file. So, you have something like ARTIST_ALBUM_SIDE_A and ARTIST_ALBUM_SIDE_B and all you have to really enter is ARTIST_ALBUM and WaveLab does the rest.
Of course, the numeric prefix is great too for adding 01, 02, 03 to the start of the file names when rendering a WAV or mp3 of an entire album but WaveLab 8.5 could already do this.