The thing is, their flavor of Agile development absolutely does work in practice, and it is hands down the most reliable way to build great software I have ever seen. However it only works if it is pretty much 100% adhered to, hence the stubbornness.
We’re currently considering PCF and their methodology. The VP pushing it has said that the cost means it has to be a success. Or, to be more clear, management knows their necks are on the block if they screw up a very overtly expensive culture change.
Not sure how honest the metrics around success will actually be...