Software has, from the time it became important enough to build businesses round, always had flaky methodologies and people who try to sell them. Just in my experience, first there were the "OO will save the world" hypesters, including the design patterns evangelists - this was the crowd Jamie encountered. Then there was RUP, then XP, then agile, now "lean software".
The common pattern in all these fads (and a quick way to recognize these things as fads) is to realize that the set of people who try to sell methodologies and the set of people who are brilliant programmers, product designers and so on are completely disjoint.
Do a thought experiment. Think about some brilliant programmers you know, the "change the world with code they write" type folks. For me these are people like Peter Norvig and John Carmack and Paul Graham and Linus Torvalds. You may have other heroes. Can you imagine these people peddling agile? Just try envisioning it. Linus Torvalds trying to become a Scrum Master?
Here is the secret. Nobody who is really good at programming/product design/marketing/business (or anything) will demean himself by trying to make money telling other people how to do what they are good at. They'd rather do whatever it is they are best in the world at. World Champions may become coaches when they are old and tired and broken down, not when they can still play and win.