[quote=Imperfectionist]
His theory isn't about the Dark Arts, though. I mean, that's the point, isn't it? That there are no "Dark Arts", just magic. You say he's quite friendly, so apart from keeping his indiscretions secret, what problem would he have with casually discussing the of his research with someone who was genuinely interested?
[/quote]

You're right - he'd just keep quiet about that part. I'm just not sure what Emma gets out of it or how they really found out about each other's oddnesses.