I imagine that the abundance of ceviches in these later episodes has something to do with the early success of Jennifer Carrol's ceviches in the first quickfire and the bachelor/-ette party. The cheftestants who are less innovative detect a preference for acid-cooked seafood and try to capitalize on their "insight". Now that Mattin has been cut for a trio of ceviches, I hope we will not be so burdened again.