With that, the hopes of the Microsoft legal team fell, as did Dertouzos's value as a defense witness. Legal cases tend to be decided by facts, rooted in the here and now. No matter what Dertouzos may think about the future course of computing, he said that the browser was currently treated as a separate product, as the Justice Department contends, and not part of the operating system. That single quotation from the Dertouzos deposition was featured in the Microsoft trial and presented as evidence by the Government. Go a little further into his testimony, though, and Dertouzos emphasizes the difficulty of drawing clean dividing lines, given the malleability of software, rendered in the digital code of 1's and 0's.
Software design is still an extremely primitive activity based primarily on art and craft.
So depending on the designer's inspiration, mind-set and approach, one of these approaches might turn out to be best. See the original article on the New York Times web site.