Retrospective topic: Let's talk about our technical practices
This topic is an opportunity to discuss what technical practices we think make the biggest impact on our performance and which ones we value.
It is also an opportunity to revisit the 'why' behind the practices. We come together in teams with different experiences and backgrounds and it is often useful to dig deeper than "TDD is good" and talk about they reasons we think something is good. That also let's us reflect and think about how we might improve our understanding. "TDD is good for..." might become the focus of the discussion. It is also an opportunity to challenge and perhaps deprecate practices that no longer feel useful, as well as introduce new methods and ideas.
At the completion of this discussion it would be a good idea to write up a charter-like list of what matters and why and share it in a public space for the team.