I searched for an example of his work that would show signs of the featureless method. Naturally, it was hard to find one, because the features were added masterfully, and look like they were there from the start. But here's an example that shows it very well.
http://www.artrenewal.org/asp/databa...e.asp?id=27638
Sargent said that one could benefit from painting blank heads for a week. In my case it would take a month, partly due to the limited time I have to paint. Still, it's time well spent.
Scott Burdick paints without features in his early stages, but the narrative gives me the impression that Sargent took it farther, and completed the planes of the face before addressing features.