(This post was last modified: 03-14-2016, 05:16 AM by Hobbyist.)
I'm not actually talking shaving soaps, just soaps in general. But yes, I have seen glycerin listed in the ingredients in some soaps, and perhaps things have changed, but from things I read the major soap makers for years have extracted the natural glycerin and sold it to cosmetics companies primarily, for use in makeup and such. What I do know is that the soaps I make at home have been providing the extra moisturizing qualities that I prefer, especially living in the dry heat of Las Vegas. It is the same with every artisan bar I've tried, such as Stirling and Soap Commander, and some locals I pick up at the artisan festivals. The two soaps I found that I was very pleased with were PdP and L'Occitane. I'm sure there are others as well, but the common soaps my wife used to buy at the grocery stores were full of chemicals in most cases, and the same with shampoos.
By the way, I'm no expert at this obviously. What I know is what I have learned in the last 8 or 9 months of making soaps for family and friends. I only have access to the same reading material as you pretty much, whatever is on the Internet and some books that are sold on the internet. I first learned how to make soaps from Soap Queen (Brambleberry) and then signed up to some boards and email newsletters and such. It's been a big learning experience and lots of fun. I don't know if you make soaps or not, but from the amount of knowledge you already have you should consider giving it a try if you haven't already.