Despite the fact that I have only played 9 rapid games, my RD (rating deviation) is incredibly low, with my rating change being at the minimum value: an 8 point change for a win/loss against an opponent with an equivalent rating. And this change happened abruptly; one game, my rating changed by ~50 points, the next, by a mere 9 points. What gives?
Your rapid RD is 49, which is pretty low. This is just speculation but the site might be using data from other pools to converge RD more quickly.
Despite the fact that I have only played 9 rapid games, my RD (rating deviation) is incredibly low, with my rating change being at the minimum value: an 8 point change for a win/loss against an opponent with an equivalent rating. And this change happened abruptly; one game, my rating changed by ~50 points, the next, by a mere 9 points. What gives?