No no, not forced ductions.
I wrote Canadian boards back in 2009 and went to school in the US, so I know exactly what you are talking about. Go to the information session the night before the test and they will explain everything. Pretty much everybody (that went to school in the US) had this same question. Basically, you place your occluder on the bridge of their nose between their eyes perpendicular to the forehead, then do your wide H's.
By the way, the Canadian boards are a joke (cakewalk) and it's a long couple of days. Good luck though! My favorite part of the test was when my patient for the fundus examination section fell asleep and wouldn't stay awake... even after me and the proctor kept yelling at him. Poutine is a hell of a drug.