> Greylisting has become pretty much useless. When I disabled it a > couple years ago, the spam levers did not increase by any measurable > amount. We now use just 3 RBLs and that seems to be a relatively > acceptable level of spam.
Checking for %ge of messages that "return after defer" I see:
WeekOf PctReturned
---------- -----------
2020-04-30 22.1
2020-05-07 26.5
2020-05-14 21.2
2020-05-21 26.5
