Martin Fowler declined to get involved in a similar effort and for the same reason. The key quote is,
“Why this is so was primarily crystallized for me by Alistair Cockburn who explained that since people are the central element in software development, and people are inherently non-linear and unpredictable - such an effort is fundamentally doomed.”
While my previous post about Alistair's paper covers much of the same ground I felt it was worthy of an update. There will always be souls who crave consistency just as there will always be salesmen willing to offer the illusion of it. Facing our own nature is one of life's hardest lessons. Some of those who ignore the human factor are optimists seeking to improve their chances of consistency, which has driven many towards the latest and greatest geegaw, a new language, a new GUI, a new design tool. Others are simply deluding themselves in the hopes that if only people would sit up and fly right (read this to mean 'do it their way') all our problems would be solved.
Studying the process of computer programming has been around for decades. Even so, we still have trouble internalizing human foibles - people aren't predictable and follow "standards" about as well as a random-walk. So the most successful way to get people to be consistent is to lead by example, blaze a trail ahead and show them the way. In this manner Extreme Programming was its own worst enemy and its own best cheerleader. By showing how a set of practices work in situ, it created a much-needed focus. The "Waterfall" model was the favorite whipping-boy, essentially dead, and the iterative approach was in its infancy. So XP served as a lightning-rod for discussions on the craft of software development. It provided an example of practices that could be emulated and provided an easy target for the doubters, disbelievers, and denialists; no doubt the negativity coming from the critics was channeling their innate understanding of the darkside of human behavior.
While Extreme Programming hasn't become the standard development model, that doesn't mean it failed. When the history of Software Development is written, XP will be given credit for re-introducing the most important factor; not tools nor process, but people.