Yep. Some well grounded people believe that these apparatus are effective only if there is a deficiency in the system that needs to be addressed. We are probably lucky 😀
Stay grounded
A few recent experiences have reemphasized the importance of good ground connections: I started by adding an Acoustic Revive RGC-24 to my InnuOs Zenith Mk3 streamer. Furthermore I added an Akiko Audio Black Box to the ground rail of my fuse box. And lastly I added a Chinese sourced grounding box to my Draytek router via USB connection. In each instance the effect was less than subtle: like snapping a camera objective into focus. I live in a single house with a very substantial grounding rod; nevertheless it seems that connection to ground via the fuse box is less than perfect. Thinking of adding grounding boxes to the speakers next.