[br3w5]

Good points - I think you need some kind of spec or something to reason about. But I don't think it needs to be complete because it is easier to iterate on software than buildings.

Taking the building metaphor, you can't clone a building locally and make changes to it, then ask another builder to review them, suggest some changes then push them out to a test environment before finally putting them into the real world. So for me, the building metaphor only goes so far but there are definitely some useful points in the article.