While this is generally true, there will always be differences between people, and this is why most of the studies involving hypnosis tend to be inconclusive, corrupted, or just conducted wrong, it does not necessarily speak of all methods of hypnosis. It's my understanding that neurolinguistics (NLP) was developed as a possible solution
http://en.wikipedia.org/wiki/Neuro-linguistic_programming
Certain subliminal methods have also had some success.