I have been in stores and found that everyone around me is being served, even people who arrive later than me, it is as if the salespeople don't seem to see me at all.
Does this ever happen to you? In a store, at a party, posting on this board etc.
Yeah, it happens to me a lot. Especially at bars, where I wait politely to be served while people scream their orders around me and get served quicker. But that's Italy for ya.
I also thought it has to do with the fact that I'm a short, unimposing guy, but it's a circular reasoning: they don't notice me because I'm small or it's me that, knowing I'm small, make difficult for them to notice me? Now I think a lot has to do with attitude, something we are not fully aware of, more than physical size.
I think people depend to a large extent upon senses other than the standard five to fully recognize and interact with other sapient beings, and that we can consciously or unconsciously control the output the response to which constitutes these senses. As you say, we can "open up" or close off. It probably doesn't work with your children because your "energies" and theirs' are so intwined or familiar on a very intimate level- you can't "turn off" that

.
I agree with you, except for the "energies" thing. I think it's a combination of behaviour, movements, body language, maybe even smell that subconsciously deflects attention. We are in "stealth" mode, like predators waiting in ambush or preys trying to go unnoticed (as apes, we are not at the top of the food chain). It doesn't work with your kids because cubs are supposed to always know where their parents are.
I practice martial arts, and while I don't believe in ki, spiritual energies, etc, I found that thinking in those terms is the better way to make my body react in a certain way. I can't think "I must make eyes contact, straight my shoulders, relax my muscles, breath deeply and be ready to act without hesitation" and make it works. Too much thinking. However, I can "focus" (I don't really know how to explain it) on my sparring partner and obtain the same results. I suppose this "shrouding" works the same way but in the opposite direction.