“the Scrum Master teaches them Test Driven Development (TDD)”

But to do that, the SM has to be a programmer. Yet I have known few SMs who were programmers.

Also, TDD is obsolete. With today’s highly distributed event-oriented systems, TDD focuses on the wrong things: integration between components are where today’s problems are, but TDD does nothing to address that.

Scrum also is confused about the SM role, and about leadership in general. It incorrectly uses the term “servant leader”, for one. According to books on servant leadership, a servant leader has both authority and accountability. And Scrum has drastically changed its mind about what the SM does so many times that it amazes me that people pay attention to it.

My advice: forget Scrum. Listen to Dave Thomas and Ron Jeffries (authors of the Agile Manifesto) when they say that prescriptive processes like Scrum violate the intention of Agile.