I would certainly be interested in trying this. My voice had always been a problem for me in the past. Even as a man my voice is quite deep and I sound very unfeminine. When I was young and going the gender fluid thing the amount of speaking I would need to do would often decide what gender role I could present as.
Although I could pass as female in appearance and body language, any more than a few words would reveal my true gender. I had tried to lighten my voice a little, but after a few sentences it would sound as though I was whispering. Situations where I knew that I would not have to say very much such as shopping could easily be done as female, you'd be surprised how far a polite nod and a smile will get you. Other situations, like taking a car to a garage I'd have to present as male. On the social side, I learnt how to keep my voice hidden. I was discreet when talking with female friends and in situations like a being in a restaurant they would subtly order on my behalf.
The advantage I have is that I am not trans. I got to choose my gender role freely, and although there some situations where I would have preferred to present as female, it was ultimately just an inconvenience. Now, as a sissy, it does not really matter. Although LadyC is quite strict in her feminisation, this only happens in private. But, just like walking in heels, it would be a nice skill to have.