@SadOnion: Specifically regarding Duke '19 RD:
a) 48 percent of the class has already been filled with ED admits.
b) The RD acceptance rate will approximate 8 percent.
c) At least 15,000 (perhaps more than 20,000) RD candidates will have some/many equal or superior qualifications (critically, both your SAT I and SAT II results are, candidly, really poor in comparison to your competition).