When you breed two dwarf rabbits, most of the offspring are dwarves. Some of these offspring have the chance to be "peanuts" or double dwarves. This is a fatal condition and tends to kill the afflicted baby, they're half the size of a normal dwarf. Other babies will be "false dwarves", these babies will grow to the size of a medium sized rabbit.
I have a false dwarf Polish. She's about 4 lbs, and has superb confirmation, she's just too big for her breed.