Board Thread:Theories and Speculation/@comment-1512913-20161119171442/@comment-4912646-20161120025819

I don't know if the "one nature in each hand" thing is meant to be taken so literally, given the number of Wood Release techniques that are performed without that process (Yamato himself even uses one a few chapters later). It may have just been a simplification he used to teach Naruto, like Gamakichi's "mixing ice cream" explanation of senjutsu.

But that aside, this theory serves as a good explanation for why two seemingly unrelated (or distantly related?) people are the only known kekkei tōta users in history. It also fits nicely with the "Selection" theme, though the introduction of kekkei mōra sort of complicates things, since it implies kekkei tōta is simply "something better than kekkei genkai". Then there are the Truth-Seeking Balls, which are "beyond kekkei tōta" but not officially kekkei anything going by the databook.