I confess, the reason I said it in a post instead of just in my head was you and Todd.

There aren't any stories I want to tell with this Supergirl. And I can't tell them with My Kara anymore, because what am I going to say? "The Supergirl meeting Rose here isn't actually canon's Supergirl, she's the Supergirl from these particular issues of these titles, here's what you need to know." Meh.

(I also can't see any reason for *this* Supergirl to be in the Cave at all, or for Bruce to let her be there. But it's just one issue. Maybe she'll be more like My Kara later on.)