This will be controversial, but I contend that a burrito CAN be too large. There is a point where it's impossible to hold and, if successfully held, it cannot ever be put down without it just falling apart. This forces one to--gasp--take a fork and knife and cut an access hatch into the top so the insides can be eaten. Am I wrong?
Depends on the type of burrito you want to make. There is a size limit for a hand-held burrito, but then there's the smothered burrito, there are no size limits for a smothered burrito. There used to be this little restaurant when I was younger that made the "Super Burrito", it was big, easily bigger around than my wrist. It was overstuffed with with picadillo, refried beans, rice and so much cheese, there would have been no way to eat that bad boy with your hands. They put it on a plate, smothered it with their chili con carne sauce, even more cheese, top it with some shredded lettuce, diced tomato, a healthy dollop of sour cream and guac, sprinkle some pico de gallo on top and a cup of their fresh salsa on the side..... dig in and suffer the consequences later.