F YOU WATCH THIS VIDEO, Fr. Gregory Pendergraft, FSSP, explains how to properly pray the Memento for the dead. One does not “fill in” the N. et N. until the end.
I’ve asked several priests, and all of them agree Fr. Pendergraft is correct. However, nobody seems to know why. If anyone cares to venture a guess, please use the combox.
If you click on the image (upper right), the 10th century manuscript contained therein seems to affirm our current practice.