What do you even mean by this? A benchmark can measure whatever you want.
Who said anything about using Geekbench? A benchmark is just a standardized test that gives a common point of reference. If you're getting tripped up on the word benchmark, just substitute test or comparison. If you run the same Handbrake encode with the same settings, etc, across a few different machines and measure how long it takes, that's a rudimentary benchmark of Handbrake performance.
Let's not delve into car analogies, please. Your underlying premise is wrong, but I believe I've already addressed the reason in the previous point.
So you don't want to measure with numbers, but you also don't want to discuss relative terms like good or bad. How are you supposed to describe performance, then?