Can scrum teams change their sprint length?
They can but it isn’t free. When we talk about velocity, velocity is predicated on a few different things; the same team, doing the same thing, in the same time box. When you change the duration of the sprint, how we approach the problem is fundamentally different. It’s not like you can just take performance, just extrapolate, slice and dice it the way that you want to. For example let’s say you’re working with a team and they are doing a two-week sprint, they are doing twenty story points per sprint and for some organizational reason they decide to go to a three-week sprint cycle. You’re not going to get 30 story points from that team. Actually I have no idea what you are going to get. You might get 25 story points, you might get 45 story points. It’s actually a completely different situation. You would have to start running a three-week sprint cycle and see what the team’s actual performance is under a three-week sprint cycle. You can’t just extrapolate it—you actually need to start collecting new data.