His expression dimmed just slightly, still not to the extent that he felt.
"That's a very special gift, Abe. A very special gift." The Doctor spoke slowly as if processing it, or perhaps trying to determine if he could somehow block it. On a dime his expression changed back to the same chipper mask. "I've got a lot of secrets. My secrets. Things I don't wish to discuss. I'm sure you understand how that goes."
It didn't work. He still radiated a sort of darkness. But at least he was polite.