This one sounds like an easy one, with a huge functional payoff.
The idea is to allow delay B to be set to either 0.612 (for example called GR-) or 1.612 (GR+) the time of delay A. As A delay time changes whatever the source, delay B time simply follows respectively multiplied by GR- or GR+. The mind boggles.. Thick lush reverb like delay that follows the tempo. Tap in a quarter note, get that golden ratio perfect fullness swimming ethereally around the beat.