I'm generally against covert hypnosis since it is usually unethical, risky, and not effective.
It's not always necessary to do formal "hypnosis" - conversational hypnosis is great. It's the "covert" part that I'm against. I'm against hiding things. I'm against there being anything to hide. I don't necessarily call attention to labeling the situation as "hypnosis" when I do conversational hypnosis, but that is because it's not helpful and there's nothing to interest them there - and not because there's important information that I'm hiding from them.