Page 73 of the Soapmakers Companion says this.....
"...the transparent formula incorporated alcohol, a drying ingredient, and they were produced at very high soapmaking temperatures, probably destroying some of the nutritive value of the vegetable oils. They were dangerous to produce, and because the formulas contained less soap and more liquid than opaque soap, they dissolved more quickly and affected the skin less beneficially."
But then she goes on to discuss how she still wanted to make them and found ways to work around all of the above problems. She talks a bit in depth about ethanol, the alcohol used in the process, and the dangers of its low flashpoint. She cautions against trying to make production size batches without extensive research due to the dangers of such a high amount of alcohol being heated in an enclosed vessel. She says the commercial makers have gotten away from these dangers by substituting chemicals for the alcohol in the process.
She has 10 pages of instructions, safety precautions and the like before she finally gives the recipe for it.
My husband has asked me to make it for him as he likes to use Neutrogena on his face. I looked at the label of his Neutrogena and there was no alcohol listed there, but after the glycerin and oils are a bunch of chemicals that I am guessing are what they use to process the soap instead of the dangerous ethanol. So.... I offered him some choices. Use my CP opaque soaps, or continue to use his Neutrogena or buy whatever other product he so desires. But possibly blowing up the house was not one of the choices.
But that's just me......