Then why list starting/ending gravities, ABV range, or IBU range when none of that can be measured by the judge other than subjectively? If they were consistent then alcohol and IBU's would be listed as low/medium/high...or carbonation would be listed as a range of volumes.
Actually, you can sort of suss out these stats at the table. IBU ranges are detectable to about +/-5 IBU, ABV of 6+% is detectable as alcohol aroma, flavor, warmth and "legs" on the side of the glass. FG >1.015 manifests as fuller body or underattenuation, FG <1.005 manifests as watery or thin body. OG can be inferred by alcohol presence and/or body.