In Accounting, a primary principle to understand is the separation of duties. The function of this principle is to ensure that different functions maintain their individual goals, as well as acting as a security measure to guard against corruption.I hadn’t realized the parallel between my professional training and SEO until I read Duncan’s article. The same principle applies for nearly the same reasons. You want spiders to understand your content and navigate your code; the separation of code and content concept that he proposes is perfectly aligned with the function of Separation of Duties.
Also, the common sense application here is that you want to highlight your content, not hide it among the HTML: A really good point to keep in mind.