I am dealing with one very mercurial professor and I had a bit of an incident with him. I think I might have offended him slightly (I told him about the deadline to submit a letter of recommendation (LOR) in the nicest possible way and yet he flared up on me). My seniors tell me that he has the habit of extracting revenge on people who ask him for a LOR if they irritate him. I am afraid I might have offended him; he kinda scares me. But he is a very good researcher in computer networks and I performed well in his class. I don't want to drop him and choose another faculty.
Now I know very well that the other two lecturers are going to rate me well, but if this lecturer gives me a bad rating will it harm my chances of getting admitted?