> A reverse centaur is just a person with a horse head right?

Well, no. A centaur is a normal person with stronger-than-human legs. That is, it's an augmented person who drives the powerful machinery underneath. Think of a person driving a car.

A reverse centaur is the opposite, namely, a machine making the choices and a frail human following them. In this context, a reverse centaur is an AI spitting thousands of LOC for a human to find the good ones.