"Treat ungraded item as zero" should not mean "place a zero in gradebook".
Having a bunch of zeros show up freaked my students out.
How about 3 items instead of 2?
Currently: 1) Drop ungraded items; 2) Treat ungraded items as zero
Maybe future: 1) Drop ungraded items; 2) Mark ungraded items with a zero; 3) Calculate ungraded items as if they were a zero