Considering last time he erased someone's mind, it killed his father and the last time Jor-El erased someone's memory, they got deflowered by Lex Luthor (platonic relationship my ass.), Chloe would have to be on the ball enough to consider sending her self time delayed emails to make sure that Jor-El or Clark arn't rinsing his memories clean... And when lana gets back?
"How could you do this to Chloe!? She's a friend! She's a human being!"
"You didn't mind when I erased your memory Lana."
"You violated me too? Have you no decency sir?!"
"Well, you were dead. I didn't think it was a big deal."
Is that why they had her out of characteristically erase that dick heads memory last week by rebooting his brain? So that this windback would be necessarily ironic?