slides are here: also linked at bottom of article
https://docs.google.com/presentation/d/1FZ6SX5rHUOYn54GDgjDZ4030ij1xU_6QeEZ_oI7HhZA/edit#slide=id.g11138c39_0_5
Changing a website for some users instead of all and evaluating results before committing to permanent change.
Explanation in common language with realworld examples of what programmers and IT project managers do. Really really long, but engaging.