I'm not surprised that they were very friendly. Most of the people in the documentary stated that Jiro has a "stern" appearance when he's making sushi. From my experience, I find that people often mistake concentration for anger.
It also wasn't as rushed as I've read, though it wasn't a full house when I went. The course lasted at least a half hour, then we were seated at a table with watermelon and tea and however much time we wanted to wind down.