User blog comment:Hidden Scorpius XI/An ever-present detail/@comment-25555436-20150120183702/@comment-25555436-20150121233638

Woah, didn't see these responses. Alright...

@Diego: I was referring to Pyrrha's tiara. Not Weiss's. Weiss' tiara could be completely normal, unlike Pyrrha's. Weiss' is an accesory, Pyrrha's is something more.

@Hidden: It wouldn't be stupid, if she can't completely control her Semblance without the tiara. There have been multiple examples in fiction of a character whose special power activates unconsciously while sleeping, sometimes with the character not realizing it.

This could be such a case; without the tiara, Pyrrha would make metal stuff fly around while sleeping because she can't fully control it. Probably not fly around to a dangerous level, but just an annoying one, for either her or others.

But of course, we're all just assuming.