"Just when I thought I was out, they pull me back in!" Step 4(g) of Pedro's Checklist: Ashenfelter's Dip with conditional parallel trends and heterogenous treatment effects

In Godfather 3, Michael Corleone bitterly complains that despite his best efforts, he has having a hard time extracting himself from the family business of running a large mafioso family. There’s a much quoted scene in which angrily he yells, “Just when I thought I was out, they pull me back in!” And that is how I feel today because despite earnestly w…