The reference to "feedback" really boils down to connecting with what is happening at the edge apex when moving the stone over it during sharpening.
This feedback "transmits" to the hand and is "felt" by the sharpener.
It is really a vibration of some sorts which tones down as the edge is refined - this is much less pronounced with the GS stones, but if you really concentrate while sharpening, you can still connect with this phenomena.
The harder the stone, the less forgiving it is with resultant less feedback transmission in terms of "finesse" - a harder stone just feels more "harsh" than a softer one.
With certain steels like carbon there will sometimes also be a certain "smell", which IMHO can also be equated to "feedback", as this smell also screams metal removal.
Confused....no problem it will get better as you go along and dabble with many various types of stones/steels....
But I got to agree, I prefer the GS stones as an all rounder. Once you get the hang of them, it's difficult to surpass....