Board Thread:Theories and Speculation/@comment-25093611-20160821131910/@comment-25122992-20160821152016

Well, I think the one of the most logical conclusions is to add to Tsunade and/or Sakura the mastery of the slug SM, which was never mentioned or represented, but by the logic of two Sannins and/or their pupils discovering and learning the SM of their summons (from toads and snakes), it seems pretty odd that we never heard about the third kind of their summoning (slugs) having some kind of SM as well.

Also, by that logic, Sasuke should receive a snake SM too in order to rival Naruto's toad SM, since he's compatible with natural energy (his body accepted Curse Mark, which is a variation of senjutsu) and thus could be able to learn it. However, in that case some of Sasuke's visual prowess should be taken away because he's already powerful enough without SM and would become a way too overpowered with it. I guess, it'd be pretty realistic scenario if it wasn't for the sceme of Hagoromo's power "Eyes-Body" divided between his sons and their descendants.