You fall asleep during your own lectures.
Is that an academic legend or do you speak from personal experience?
My own version of this is having the out of body experience where you hear yourself talking and feel powerless to stop the rambling.
I call this "being in the zone." If you perfect it, you can write whole paragraphs of your next paper in your head while lecturing. This is multitasking.
Oh, I forgot about that. I used to teach six sections of the same course. So by classes #5, 6, I'd be going on auto-pilot. It was truly bizarre to have my mind wander off, only to be listening to myself talking like it was someone else.
I thought I was the only one who did that. Yes, I only have three sections of the same class, but yeah, I definitely tend to be outside, listening to myself, and wondering, "Doggone it. How much longer is she going to drone on about that topic? I'm tired of it and want to go home." What's sad are the days that I find myself thinking that halfway through the first lecture and realizing that "she" is me and I'm doomed to listen to that topic a second and third time.
One of my students was distressed to realize that I don't give exactly the same lecture to all three classes (she learned this because she came to another section to ensure that she didn't miss the lab, then went to her regular section the next day, and the lectures overlapped topics). However, she was primarily disturbed that the numbering of topics didn't line up. I had six main topics on Thursday and seven main topics on Friday because the discussion on Thursday made two topics intersect so I just eliminated the lecture on a topic that we already covered during discussion. I saw her notes and was amazed that she even noticed a picky detail like that considering the large factual errors that she had in the notes, which should have been noticed on the second time through by comparing what she wrote to what was still on the board.
