@rlinfamous, if minato was sealing the kyubi's yin in himself then the dead demon seal would not be necessary. and by using dead demon seal anyway, sealing the yin within himself is redundant as the dead demon seal was, at the time, the most secure sealing method, simply sacrificing his life to seal the yin with dead demon would already satisfy all requirements he had in mind.
think about it, he likely believed that since naruto was an uzumaki then he would eventually discover the key to dead demon and reclaim the yin. if minato had actually sealed the yin within himself then it would be impossible to obtain unless minato were to be revived. minato had no way or reason to expect being revived and his chakra deposit in naruto stresses that fact. he was even surprised when he was summoned and freed from the seal because without edo tensei, minato would have then gobe to the pure world, not the uchiha shrine! the yin was sealed in the dead demon for safe keeping until naruto could reclaim it. most obvious is that if he sealed the yin within himself then he would have absolutely nothing to seal away into the dead demon! it would have been a suicide without any sort of object or logical cause, outcome or effect. it borderline the absurd :/
"along with myself"