It requires a mental switch in focus. For me anyway, it's not a big difference if it's between working on implementing feature A then switching to working on im

It requires a mental switch in focus. For me anyway, it's not a big difference if it's between working on implementing feature A then switching to working on implementing feature B, and working on feature A then switching to doing a code review for feature B, but I probably take my code reviewing responsibilities more seriously than most (e.g. I always checkout the branch locally, ensure it builds and runs etc.).