Actually I do, which is why it's far more likely for a concussion to be caused by an elbow than by a wrister hitting a goalie mask. And okay, so you think a wrister is going to cause such a whiplash? A puck just doesn't have enough mass.
It's kind of funny seeing you first saying I don't understand concussions, and then giving examples that support my point. A ring hitting a specific spot is the very opposite of a goalie mask, which is designed to spread the impact onto the entire face. It's very different from getting hit by a puck raw.
Of course, it's possible to get concussed by a puck shot at the helmet, but the example right there isn't a particularly hard shot and goalie masks are designed to absorb such impacts. I guess it would technically be possible, but far less likely to be the cause than an elbow to the head.