This one has bugged me for some time and I heard a reference to it again the other day which has prompted to me ask about it here.
At last years Agile Development Conference in Salt Lake City, I was on a park bench panel with several others on Adopting Agile. The panel had been running for maybe half an hour and I happened to have one of the four "speaker chairs" at the time and I'd just finished speaking quite a bit myself. Alistair Cockburn came in and took one of the speaker chairs. He said that he'd just come from a presentation by Roy Singham, CEO of Thoughtworks, and Roy had said that to do Agile required 50% of the people to be experienced in Agile. Someone in our session asked Alistair if that meant 50% of the people had to be trained (e.g. had to have done an XP course - for example) and Alistair answered no. Not just do 50% had to have done an XP course, they had to also have done an XP project.
I heard just the other day that a "50% must be experienced" assertion is also made in the Scrum book (I don't have the book so I don't know if this is true or not. Also, FWIW, I quite like Scrum).
I am intrigued by this because I'd like to understand it better and learn. It just doesn't match my experiences at all. However, I am not interested in a "FDD is better because..." or "method x is worse because..." type of discussion. I'd just like to understand better why such a high number is required.
My experience is about 20-25% or 1 in 4 or 5 people need to be experienced. However, I can qualify that to be 1 in 4 or 5 need to be what I call an A-class. That is, they do not even have to be FDD experienced. When I do an FDD project and the majority are not FDD-experienced, I run my 5-day workshop first and then proceed to the kickoff and the first FDD process.
This isn't what I think works, it is what I do. It is my experience across many projects and many years.
So, what are your experiences and thoughts in this regard?