But… lineage and heritage are synonyms.

I don’t doubt that this is something Luke could detect through the Force. He was in Palpatine’s presence before and would have PTSD over the feelings associated with him after being tortured by him. But Leia never has been anywhere near the guy. That’s the issue I have with it.

I was saying that she could definitely detect a great source of power in her heritage, which could lead to corruption, but I personally don’t see how it’s possible she could narrow it down 100% on “Palpatine”.