We completely agree, and will probably change that in the future. We force signup now for 2 reasons: 1) Right now the most important thing for us is to establish product market fit. And the way we do that is by sending a survey after you take a course, and by seeing where you drop off - both require signup. 2) It lets us keep track of your state (so you can stop, start, come back), and allows you to participate in the exercise / notes, both key pieces of functionality in taking the course.