Can a premium HDMI cable outperform a standard cable?
You would do a BERT (bit error rate test) on the cable. Better yet, look at the eye diagram at the far end of the cable.

HDMI is a digital format, which means that there's a threshold effect &mdash; cable quality does not affect the picture quality at all until it gets so bad that it actually causes bit errors.

"Premium" cable is (supposedly) built to tighter tolerances (reduced ISI), with thicker wire (reduced attenuation) and/or with better shielding (reduced external interference) so that you can have longer runs of it before that starts to happen.

Bit errors flip individual bits, and the visual effect depends on exactly what that bit is used for. A bit error in one of the MSBs of a color channel will cause a pixel to be unexpectedly brighter or darker than it should be &mdash; this is commonly called "salt and pepper noise" because in a B&amp;W system, the random white and black pixels look like salt and pepper have been sprinkled on the image.