I would love to hear more about that.
You can start here: http://psychology.about.com/od/nonve...erbaltypes.htm
My old sensei has been training for 50 years and she said she got her wallet stolen twice. If 50 years of training don't give you the sensitivity to know people are trying to rob you, then I call BS on a shodan training for 16 years and claiming he has it.
There are people who are "completely deaf", there are people who are not "deaf at all" and everything in between.
Maybe your instructor is a natural born reader of non verbal language who has fallen in a post hoc ergo propter hoc fallacy (I can read because aikido) or maybe he can't read and is BS'ing you.
I have serious reservations about aikido training as the main cause of his sensibility (if he really has it) to non verbal cues.