I think that a class is a great idea and usually a wonderful learning environment. I learned from a person and don't know what I would have done if I would have had to rely on the internet (wasnt even one of those then, lol) or choose from books, never knowing which info is correct and which isn't. So many contradictions in books today, or an untruth that is repeated (verbatim) in several books. Definitely I would opt for a class, given a choice, and I think most are pretty good.....although we have heard some horror stories! But I am sure your class was better than many since it was a chemistry teacher teaching. He just didn't consider the scent to be an "important" detail that he needed to study or pass along info on. That is my pet peeve, many teachers don't understand that it is more than just dumping some in until it smells good.
I actually read (on a professional group discussion board) a man giving advice to a newbie about fragrance, where he said to "just dump some more in til it smells good to your nose." No amount of comments/arguments could get him away from a nose being the best judgment for the amount of fragrance to use. And he is not alone, so I tend to crusade a bit, but it is an important issue that is often overlooked.