So I'm trying to learn what the boiling water does for dough like choux pastry or the various Chinese doughs that do the same thing. The Peking Pancakes, Green Onion pancakes and a few of their dumpling doughs use the boiling water technique. I checked my copy of On Food and Cooking by McGee, but he only mentions that the dough is cooked twice. Once while making it and then again for final form. He doesn't describe what it does for the dough. My first take on it is that you get the effect as of a higher hydration with less water. That's how the dough seems to act to me anyway.