You know, it is a great book and I love Jamie's interview and the "duct tape" style was used well at Netscape, but just because the guy doesn't writing unit tests or use higher-level abstractions doesn't automatically make him better than other types. Some of the smartest programmers I've met have been religious about TDD and strict formatting and commenting and as a result maintain and work on some incredibly large…
You can never say this is the ONE true way to develop. Do what works for you, but just be aware of other points of view.