I never thought of that my concern was with the fact that Kazuki was fine after that sword cut through everything between his skin and where his heart should have been (lungs anyone).
But then again one sided physically inexplicable powers are nothing new. Goku can Kamehameha away from a stars gravity but not go anywhere when he's shooting at other people (I think when he first fought Vegita he shattered the pillar he was standing on by firing one upwards though).