That is still beyond me. From what I've seen in some drafts claiming to use it, it's stacking a whole bunch of EQs or multiband compressors on top of one another, but when I tried doing it, it failed.
It does that without influencing the frequencies. If I had to describe it in simple terms, it's like a comb-filter-ish thing completely reserved for phase, or like supersonically fast phaser, not affecting any pitch.