Yeah, the most fun use of Disguise Self is usually to copy a specific person. If there were an action you could take to study someone - and that would store them away either for a certain amount of time, or maybe you could only remember a few people at once and have to forget someone to learn someone new. That would be really excellent and would probably be a huge pain for Larian to update all of the possible dialog trees.
Which is probably why they're absolutely not going to do that, and why I'm absolutely not going to blame them if they run away screaming.
