> My grandmother made those in her Sunbeam toaster before loading them with room-temperature butter and Laura Scudder's smooth peanut butter. (Yes, my grandmother kept butter at room temperature but refrigerated the eggs. Go figure... grandmothers.)

American commercial eggs (and this has been true for a long time) need refrigeration because thet are washed, which reduces surface pathogens but compromises the eggs natural resistance to environmental pathogens and spoilage. Meanwhile, in most climates, butter is safe out of refrigeration. So, your grandmother was doing it right.