[sheepmullet]

"Perhaps I'm just biased, because I've been working in excellently-managed agile teams that have been delivering software very effectively, and have seen how useful Scrum has been as a framework to manage the complexity of planning it."

I'm lucky enough to have been in the industry before agile and scrum were popular and back before the agile days I worked on excellently managed teams that delivered great software effectively. I've also seen a lot of agile projects crash and burn.

At it's core agile is a small set of guiding principles. Principals I'm sure most of us agree with. Yet it's hard to sell these principles to process heavy organisations. I've seen it fail time and time again despite the efforts of top consultants and coaches.

IMO, agiles real success has been in giving structure to cowboy driven teams. Teams that now actually write requirements down. You could never convince these "cowboys" to write an SRS... But a few user stories... That's more realistic.