Well one, like Moonlight said, not throwing it in on top of shit would've been a great way to not make it seem like a cheap trick, but two, how about Lisa could've said something? She doesn't even fucking say anything about it. Shadow Lisa says it and Lisa just blinks it off. But they should've laid the foundation for this shit well in advance, made Lisa address it, and then moved on if they were going to do this. You don't half cock into this. Instead, Shadow Lisa says it, Lisa doesn't hear her, and afterwards nobody even says anything afterward. No "Oh gosh, Lisa, I'm sorry." No "Holy SHIT Lisa." Nothing.
What did I expect? I expected something less lazy.
I mean, there's no real reaction to it. In Persona 1, 3, and 4 the cast reacts when things happen to each other. When Yukiko is melting down, Chie has stuff to say. When you find out about Maki both Mark and Nanjo have important things to say to her. But in this case it's like a long ass silence on the party's part followed by one huge forced smile and generic "Ohoho I will be the winning girl!" talk.