From the descriptions, it sounds like fear from people's own subconscious minds is rising up to affect them this way, not the intentional actions of BEKs, but why? They wouldn't deliberately scare people, if they wanted to be let in, would they? The other thing is I don't believe hypnotism is a good idea. It can affect and reduce the power of one's own Will. That can't be a good thing. If a person had a strong enough Will, he couldn't be hypnotized anyway. Neither could he be driven into fear or posessed by someone with a stronger Will and mental power.