[Heaven's Night]

That's interesting. But I'm sure it will be interpret as: I munch licorice, I'll get a pretty female voice in a week, or something like that. Its not that simple. Voice formation is one thing and that alone is quite a deep subject, excuse the pun. Firstly pitch alone doesn't do much, resonance or "voice colour" does way more than that. Female voice has both higher pitch to some extent, and higher resonance. Then to top it off there's speech nuances which differ a lot depending on language, dialect, age of the person and so on.

The point I'm making is that even with vocal chord surgery alone, voice will be distinctly similar as before even when pitch has gone up. Resonance can change dramatically only by practice, it goes along with pitch and minor change to latter wont make or break it.

So if there's something that actually physically alters vocal chord function, that's quite darn neat. But it will never be a short cut to cute feminine voice as that WILL take a lot of practice and some might need the surgery. Which btw, typically shortens low range, but doesn't do a thing to higher sounds. Latter is pretty much solely practice.