
Originally Posted by
Phoenyx
No reason they couldn't, but if they did -and- they had the knowledge/ability to use it as effectively as Madara or Orochimaru (or Kabuto?) I'm thinking we'd have heard about it. And maybe we will. For all I know Madara could end up divulging all about failed experiments by others that led to his success or something like that. But the way I interpret Itachi's explanation of Izanagi and Izanami is one that is really old. Like way before Konoha. So Madara hadn't been born yet, and no one else had a raging hard-on for any of the Senjuu yet so "being inside me forever" wasn't on anybody's mind.
Again, just my interpretation of events thus far with the knowledge at hand. Also, it seems a little odd to have a technique that requires the combination of the two strongest bloodlines in the series defeated by one that only requires one of those bloodlines. And not only that, but the nature of Izanami was to allow the person stuck in the loop to break free by "repenting" or whatever. Would the Uchiha really want all these folks that were abusing Izanagi (in your case with their combo DNA) running around just 'cause they said they were sorry one time? For me, it doesn't line up.