Re: Removing distraction = good
If a vehicle is indicating to leave the roundabout via the exit before yours, then it's perfectly reasonable to begin to move onto the roundabout. It's the LACK of indication that's an issue. There's one notoriously choked up piece of road near me and through flow could be 10-15% higher if drivers indicated to leave the roundabout allowing vehicles entering to move forwards and into their exit lane (which is an immediate left for them).