That is all well and good, but my original question was whether in some cases there shouldn't be a more immediate intervention when it's obvious that an announcement hasn't been delivered intelligibly. In the case I mentioned it should have been clear to the senior crew member that nobody who doesn't have superhuman concentration skills would have been able to piece together what the announcer was saying, yet she did nothing and left the culprit in charge of the rest of the announcements for the flight. This is what I found surprising.