This detail shows how the fumed silica gel changes the consistency of the paint. On the left is pigment mixed with linseed oil. On the right is the same paint mixed with about 1/4 part silica gel. The workability of this is just magnificent. It is fluffy and lightweight, has no odor, and stays where you put the brushstroke. It does not level out or run in any way. As far as I can tell it does not alter the appearance of the paint surface such as a medium with a varnish would. The benefits are bulk and excellent handling of the paint.
In this detail of a pomegranate from my Greek 5th century BCE painting, you can see how the seeds stand out. I layered the paint/silica gel mixture one on top of another to achieve the appearance of seeds as they are on the fruit. Then by changing the color, values, and consistency the texture built up across the surface of the canvas.
Again, it would be interesting to hear from any of you who have experimented with this medium.