I love this approach, but let's be real: this is a privilege of small teams/organizations. It is also what becomes possible once you find yourself in a team filled with highly experienced people.
Jason and 37Signals have always influenced how I run my agency, and I generally agree with most of the things they preach. In my quest to implement some of their methodologies I've found that some are simply not suitable outside an organization such as 37Signals (small-ish, rich, many experts, very special culture).