mostly, the tense grips i've run into have been attached to tense arms.
either pushing or pulling, or trying to hold you still.
and probably about half of the loose grips i've run into haven't meant it. they were just kind of killing time.
tense grip connects you with the opponent's frame. even if their arms are kind of loose, it can at least give you the elbow. loose grip, if we're talking about sloppy loose, can give you their wrist.
now it's time for the obligatory taiji note or question about the difference between grip/grab/grasp, and sticky energy. and the weight of a stick of butter, and adhering to the opponent as though you're slapping a wad of biscuit dough on their wrist. and the difference between the way a baby grabs your hand, and the way someone uptight does.