Well, I have to say that the first parts of your post/questions is really not clear. So, I will comment on the last part...which I guess you were leading to anyway.
I will summarize what you wrote: "Do you think hypnosis can be resisted consciously when it is not attempted in a formal way? Is difficult to say where social interaction ends and hypnosis begins?"
I, personally, are a bit of a rebel on this topic. Researchers want to say that hypnosis is this or that measurable thing. My observations are that it is very difficult to say where social interaction ends and hypnosis begins. ... In fact, it is pretty close to impossible. But this is based on my idea of communication. All communication manipulates (not in a bad way necessarily). I want you to tell my how much your computer costs and so my questions focused your mind on that in the process of talking. That focus is manipulating your attention no matter how you slice it. If hypnosis is a heightened state of internal concentration, then the more my communication heightens your internal concentration...the more it is hypnotic. So the line is pretty darn well blurred between 'normal' conversation at times and deliberate 'formal induction'. I don't know that many would disagree with me on this...Andre Weitzenhoffer and Erika Fromm even agreed with me about it. Yet, when you say normal conversation is hypnotic conversation...suddenly lots of controversy rises. I think it is merely a problem with how we each define hypnosis. Researchers need to make a very very clear distinction on how it is defined. This is okay, as they want to be able to carefully measure something unique. Nevertheless, it makes what I have just said invalid.