Any man that has ever amounted to anything has never done a great deal of detail work for long periods at any given time. He needs his time to reflect. He does not do his duties today in the same way as yesterday, but as the result of deliberate and concentrated effort, constantly tries to improve his methods
What is detail work?
I don't find it that strange. It's talking about "continuous improvement" it seems. If you do the same job over and over and never improve on your techniques and methods, that's pretty sad.