"Glad to be of service." He might leave out details here and there on subjects he'd rather avoid, but the one sin he is not very guilty of is deception. Cultivating his manner of speech doesn't count. Probably.

"You could practice by making up extravagant lies, but I can't promise I'll believe them." Could be a hilarious exercise, though. "Though really, anything you've said today could be a lie and I wouldn't know. You're free to try and sneak them into conversations, as long as it's nothing important. Keep us all alert."

He might be joking, but he also might not be.