Since it's Passover, I've been making matzo brei this week. Yoyo has told me that she never had as good a matzo brei as when I made it in 2007 when I first met her. I realized this morning why that might be. Back in 2007, I had a small omelette pan(~5 in diameter), in which I cooked the matzo brei. I think I lost that pan in a move that Fall and since have been cooking the matzo brei in larger pans. The issue is that the egg does not get as fluffy when the surface area in contact with the pan is large relative to the amount of egg in the pan. The same would be true for the production of a fluffy-and-textured vs a thin-and-crispy omelette. This is why at Charlie's, where you can find one of the best omelettes in Boston, they make their omelettes in very small, slightly deep omelette pans. The omelettes are fluffy and rich, then finished under the broiler for a crispy exterior.
For the matzo brei, a fluffy egg makes all the difference as the bits of matzo hang in a sort of egg suspension. Without this suspension, the mixture becomes kind of slimy and runny, and when overcooked, almost inedibly bland.