Two days ago, the very last lesson of Prof. Ben-Porat's course on intertextuality and the western canon took place. Per our agreement, I e-mailed her my lesson notes to review, and, it being the final lesson, included a few words of appreciation and thanks. My gratitude is immense: this person impressed me on many levels, from personal grace through erudition to literary insight, and her class was simply enjoyable and enlightening throughout. But my phrasing was polite and dampened, following ygurvitz's advice; he said that if I enjoyed her class so much, I may very well want to take a seminar with her next year, and so it would perhaps be unethical to break the academic barrier at this point, and may place the professor in an awkward situation next year.
So, she just replied and thanked me for "my kind words", but also wrote:
If in spite of my failing memory and the university's 'recovery plan' (which entails retiring people like me) I'll be teaching next year, I'll be delighted to have you as a student once again.