User blog comment:Mr Easter/Could Kuina be tashigi/@comment-2109035-20131214234718/@comment-972068-20131215001526

Here's a little theory I have, IF Kuina is alive and she's really Tashigi.

After falling down the stairs, Kuina got amnesia. Koshiro, being the teacher of both Kuina and Zoro, didn't want to make him believe that Kuina lost her dream to be the greatest swordsman. If Zoro knew she just lost her memory, he'd probably think "What's the point of fighting for my dream, now? I have nobody I promised it with." So Koshiro faked her death and told Zoro to keep going. Koshiro also sent Kuina to another village, where she was raised under the name "Tashigi".

But that's just a theory of a theory. I'd rather her just be dead.