Notice Bill’s palette knife technique. He is allowing the paint to be pulled off the knife onto the canvas. There is no heavy pressure on the knife, just a delicate, light touch. The paint is thick enough, and the under layer is thin enough, that the two layers to work together beautifully.
This is a technique well worth practicing if you want your mountains to show that beautiful breaking pattern of the paint. Like a fingerprint, your mountains will be unique. And we know that uniqueness sells!