For the exercise organizers, it's very useful to know how many different students are in the lecture and ask questions. This way they know where and when more tutors are needed. To give them this information, we would like to save your username for the exercise to filter multiple requests from you. Dont' worry - we just tell them how many different people, but not who exactly attended the lectures. Is it okay that we save your username to count how many unique users were in this lecture? This won't have any affect on your requests or wait time.