to be honest when i read the manga just now i totally misunderstood it the first time, that why i was wrong, but am i really? is it impratical that to get the sages eyes(rinengan) you need the sharingan plus + senju dna (blood, power,strengh) whatever you wanna call it.Ok, so you're theorizing. That's fine, but that's distinct, and you're assuming a + b = c. You have to be careful when you substitute theory for facts, and state clearly when offering theory in their place.
Peace