I've made the crackers dozens of times now, and found that they're even better if you roll them out twice as thin. That is, the recipe tells you to divide the dough in half and roll out two large squares--I've found that they're even better if you divide the dough in fourths, and roll out four large squares. You have to remember to pay attention to the ones in the oven--being so thin, they can brown too much very quickly, but they're so much better thinner. They brown evenly, and each and every inch is crisp.
I've also given up on the scoring and trying to get them square--we just crack them up into pieces. It's faster to the table that way!