Dave hadn't thought about the Morgana thing. Truth be told, he hasn't thought about that for a while. Call it a defense mechanism.

He makes a face. "Well, I don't know what it's like in your... world..." He falters on the word, the realization of what's happened hitting him all over again. "Give a time traveler a break, jeez."

He then follows after Horvath, bottle of water still in-hand, with the most understanding look he can manage plastered on his face. "It's cool. No rush."