I know personally Fowlers articles, some of the folks we hired who were former Thought work-ers, and my experience running through agile, SAFE, classic project management, and XP; nothing came close to the XP method.

It was put up or shut up. If you said you could do it you can almost guarantee someone would ask you to show them and explain.

A lot of "knowing something is not the same as knowing the name of something"