As he cleaned up the tray and set it aside, he shrugged. "I may request another sample later as corroboration. Scientific research requires replication for something to be valid, so it's a lot of doing the same thing several times and hoping that your techniques are as error-proof as possible." Straightening up, he adjusted his glasses, looking down at her as she asked her question.
He got a briefly sour look, though it wasn't because he was irritated with her. Oh no. He was irritated with this variable. He sighed. "I recognize that this may happen, and if it does, I will lose you as my control subject." He paused. "However." His expression brightened just slightly, though it was still fairly dim. "If that happens, I now have a sample from you before the change and will take one afterwards, which will give me a unique comparison, and could make you extremely valuable."