> I still don't understand why Tocharian being centum in the east would be considered to contradict the theory that the centum/satem split was one ancestral inn

> I still don't understand why Tocharian being centum in the east would be considered to contradict the theory that the centum/satem split was one ancestral innovation as opposed to many independent innovations. The way I understand it is that Tocharian was an early branch from PIE (reflected partly in its grammatical divergence from it's relatives) that preserved the original centum pronunciation, and that the centum/satem split we refer to today came later. I'm not sure if the other commenter meant it in that way, though.