He means that in mods you can disable the ability to move your joints after they've been detached from your main body.
Ex. if you kick off my arm at the shoulder, I can no longer move my elbow and wrist and then grab you for points.
Same general thing would happen with this since fractures are fairly common, and the inability to grab would just ruin gameplay since if you were about to win and your wrist got fractured, you lost your grip, instant loss. No one likes loosing, unless they're just messing around.