Radical is from a latin word meaning root. Going to the foundation, the substrate, or root is what shikantaza is. There is no mundane sense of progress particularly. If the thinking process shows up as some kind of result, you have work to do. Just receiving and not being too concerned about how you feel about it is the radical meditation of shikantaza.

https://www.youtube.com/watch?v=fJgO7oaRlKM