Yeah I have noticed if my girl sits quietly while being held, then stretches her head/neck way up high and starts smelling things, it does seem she must be relaxed. In the wild stretching like that, raising ones neck and head up several inches would probably not be the best survival strategy when frightened.
(Did i say i was not hijacking the thread? Guess I lied, but this is so interesting and I hate to post tons of newbie questions in brand new threads.)