Really good read all of this. Enjoyed reading your posts especially Norm.
I remember reading something about a self glazing clay that while it was drying it had some water soluble flux that was brought up to the surface. This then went onto turn the outer layer of clay into a glaze.
Have I just been confused in my reading or is this a different technique? This way seems to be making a clay that is 100% glaze/clay hybrid.
The 'soluble salts rising to the surface during drying' sounds like this is an Egyptian paste recipie you may be thinking of, which is a low firing self glazing body (often coloured turquoise though white and other colours may be had) the salts form as the 'glaze' layer over the form. This body is used for smaller decorative pieces rather than functional ware.
Anna's query is the 100% clay/glaze hybrid body.