Board Thread:Naruto Discussions/@comment-25645405-20141128183407/@comment-3279282-20141202030752

Yes. He doesn't need to state that you can't combine the five natures with Yin or Yang, because that is not how advanced natures are created. You probably could apply seishitsuhenka to Yin-Chakra, but you can not combine Inton and Katon, for example, because Yin and Yang are no elemental natures.