I think the reason that Kariya didn't show his doll is because when you merge with the doll you can control whether you use it or not. So he just always had it available to him, but kept it away. What's her face at the beginning merged with her's and needed the power immediately to fight with Kariya. So that is why. I don't think it is permanent always on sort of thing even merged. That is my thoughts anyway.

We've got 2 episode left before the Bount Arc is completely finished. The new season of Bleach is supposed to be starting in Japan soon. They are going to have a new OP I would imagine. So I can't wait to see what it is going to be like. And Adult Swim has it marked for two episodes of Bleach starting in three weeks. So I don't know what they are planning and if they are going to be going to new episodes or not. I hope they do, I want to see the episodes that I've been reading in my manga.