She studied at the University of Wisconsin and Perdue, and has worked in Albequerque and Stanford University. Since 1978, she has been in private practice. At a seminar at a past California Dreamin' convention, she elaborated on female voice and communication behaviors. First, there is no one specific type of female voice. All are female, but each is very different.
Falsetto is high, thin and tinny sounding.
But there's no power to it, and you can't get melody or inflection. Speaking up there habitually is not the way vocal chords were meant to vibrate. Breathiness is associated with Marilyn Monroe or Jackie Onassis. It may sound inviting and sensual, but the balance of breath to tone is out of whack. It's far better to develop a female-sounding voice within your range, than to go outside of that range.