I completely agree with your calculations. Even though I interpret the numbers differently. If you look at the first time it happened, you had the first probability once. And after that had happened it's exactly the same probability again for that case to come true. I know, if you stand at the beginning it's the product of the probabilities. That's why I find it not that improbable that this has happened. If you go to a casino and stand there for the right 8 times, you might see one color be selected every time. And a roulette table that is spinning all evening has a high probability to make this happen. This is just a different approach on this case. Your calculations were completely correct with the condition we had to choose since bungie didn't specify if there are weights or so. Edit: typos