To read a dog is not simple at all. Is not an ability you can pick up in a few days, weeks or even months. In my experience it takes years of study and application.
All the shelters look the same, all the dogs seem the same dog, the same face behind a mesh. Those snouts get to you only when you cross that gate, when you enter their world.
Control isn't a good or a bad thing, per se. We need to analyze the context in order to get its meaning in that very situation. And once we get it, we have to respond properly. To prevent the dog to control things, or even people, in such a stressful situation wouldn't help the dog, nor its trust and bonding.