My experience: Had '99 2.5 GV, put in ditch avoiding a pedestrian in my lane. Bent every side but the top. Forward momentum was stopped and I was spun around by a post that hit just inside the tire line on the drivers side of the bumper. No bag!
Later, daughter puts '01 GV into a railing and walkway. Near dead center on the bumper. Another inch and it wouolda been toast for driving. My Ac condensor is an arc instead of a straight line. Anyway, no bag deployment when we hit at about 5-10mph. Discovered that the sensor is about 12-16 inches to the passenger side of the bumper from midline.
I would guess that it takes one heck of an impact, or it needs to be triggered from directly in front. (I am presuming that my pre-owned GV's have working air bags.)
I do minimal off roading, and I do not even think about the air bag then.
Pat
Pat