Burnwinter the rule is that if you're going down like that you have to support yourself with your arm, so it's not a penalty. However, a side effect of that rule is that you can then basically go down and use the arm on purpose because you "have to support yourself". Very stupid rule the way I see it. Or at least lacking in nuance.
Edit: If you referred to the Maguire one, that is. But thinking about it, they probably only showed the Dorgu one in the highlights.