But this an overly-academic approach to the problem. Your interviewers will still write in whatever they write, as colored by their perceptions and rapport with you. If they write that you had a bad interview, then that's going to poison the HC. There's no way around this.
The HC appears to serve only as a layer of noise/a random selection filter to determine who is actually offered a job.
It forces you to back up your opinions with data, though.
As long as the decision is made by humans, you will never get a completely unbiased result, because humans have biases. It's the same in every field - people pretend science is objective because it relies on data, but if you read Kuhn, you'll see that a lot of science is personality cults and subjective opinions and schools of thought. People pretend Google's search algorithms are objective because they rely strictly on numbers and data, but they're written by humans, and humans choose which data is important.
But that doesn't make the data useless. The act of being forced to support your opinions with data makes you dig much deeper into them, and surfaces relevant information that'd otherwise be ignored immediately because it doesn't fit your preconceptions.
Think about science vs. polemics. If you're actually doing original research in a scientific field, you'll realize that there's a lot of uncertainty hidden behind "the scientific consensus", and a lot of other ways of interpreting that same data. But that doesn't mean that the scientific consensus is wrong. It may be wrong, but it's probably less wrong than whatever vitriol Ann Coulter or Glenn Beck or Michael Moore is spouting at the moment.
The HC appears to serve only as a layer of noise/a random selection filter to determine who is actually offered a job.