Yeah I know what you mean, I'm in awe of the author's ability to create the perfect environment for his team to succeed. Part of the key, I think, is that he was dedicated to caring about every factor that might affect success (customers, project management, design, and the other categories from the list), which left his team free to execute on the technical aspects.

I also think we might be underestimating how much one could do with one year, a relatively well-specified problem, and a team of three super motivated and intelligent coders.