Mills is excellent in articulating information during lecture. It's not the conventional "derive equations on the blackboard" but rather "reading" from his textbook in a condensed manner followed by insightful comments. I know many people think its not the most effective method to lecture, but it helps cover a lot of material in 10 weeks. The best way to study for any Mill's course is to write notes in your textbook based on what you understand. Ask him any questions you have in office hours. Most of the time, they are empty until exam time.

He is very concerned about the students learning as long as they are interested and have questions. So come to his office for a chat. It doesn't have to be about heat/mass transfer, you can talk to him about anything.