It's not a technique, it's a natural outcome of statistical modeling.

It doesn't get used because people are innumerate and reactionary.

The technique I'm referring to is including race as a factor, and then instructing your model to disregard that factor. Not being race-blind, but being race-aware while attempting to be neutral to race.

Yeah I think this is an interesting idea but I don't actually understand how the great-grandparent comment believes that this could be done. I don't think it works in a strict Bayesian sense. You would have to go out of your way to instruct your model to operate correctively