It seems that heros like XF can take and dish out palms with the force of tons behind it, but only when its something like a fist or palm or kick with that much force behind it. If a 2 ton rock were to hit them, even if they were ready for it(but not allowed to block or deflect it), they'd probably get seriously injured. Why is this? Does inner strength only blocked other inner strength attacks? And does this count if someone throws a rock instead of directly hits them? If this is the case, wouldn't it be smart, no matter how high your martial arts, to carry some sort of weapon to be able to hurt an opponent? It'd be silly to rely on your palm and fist skills when they can be neutralized completely by someone with comparable strength, when carrying something like a little hammer even is enough to seriously injure them if you hit them with it instead of your palm.