Article About the Evolution of the Shanahan System and What Makes it Work

I thought this quote from the article was a good explanation of the general concept of the offensive system:

"Everything is on the table. Because the keystone of the 49ers offense isn’t any one thing. The keystone of the 49ers offense is that you think it’s one thing, and it turns out it’s something else. It’s putting a fullback on the field to make you think run, so that they can pass. It’s bringing wide receivers tight to the formation, so you think of out-breaking routes, so they can run in-breaking routes. It’s motioning to a formation that you don’t think is empty, but actually is. The keystone of the 49ers offense is your perpetual wrongness. Shanahan better. Skill issue."