Every clipper has a line.Gain reduction won't tell you where it is.
Verge measures the harmonics your clipper is adding, band by band, and weighs them against how much of your own mix is already covering them up, so you can push with more confidence.
Ears lead, eyes confirm.
Push the clipper with your ears the way you always have.
Audibility Check indicates when your generated clip harmonics start to poke through the dry signal.
Your ears don't always hear audio the same way twice.
That's just psychoacoustics. Ear fatigue and auditory masking can obscure your objectivity. Audibility Check doesn't get tired and doesn't get fooled.
What it's doing
Verge subtracts the processed signal from the dry signal in order to isolate the harmonic content being added by clipping. That content gets split into 24 critical bands, roughly the way your own hearing divides up the spectrum, and each band is weighed against how much energy the dry signal already has sitting in that same band.
What it won't do
It won't tell you what sounds good and it isn't trying to. What you're getting is a second opinion from something that isn't three hours into the same mix, on a decision that stays yours.