[garrettr_]

“What this does is free your co-worker to be 100% honest. They don't know which parts of the interview were really you trying to perform well.”

Since there was no mention of it in the post, this is called “randomized response,” and is a building block for modern privacy-preserving protocols e.g. RAPPOR, which is used in Google Chrome: https://security.googleblog.com/2014/10/learning-statistics-...