I never heard that advice about bared teeth, always they got the jump on me, so it was not a question of passing by. Some rather large teeth, too! That was dreaming in REM sleep, not what I understand as journeying.
I assume you meant "knowing the difference" between "entities in their own right" and "baser instincts and desires". They do seem to present differently in dreams, from what I can tell.
Went to a wolf talk a couple years ago, and the presenter explained that wolves bare teeth at first meeting, and expect you to do so in return. If the human doesn't bare teeth, the wolf will nibble on the human's lips to get him to do so, I think so he can see what the human has. Sort of an etiquette, not like showing fangs and snarling.
Blessings,
Aronaya
