Hi Rebecca:
I think I agree with the essence of your comment. The reason the students are there, and our relationship with them is as instructor, mentor, facilitator, teacher. We are not there to demonstrate our (perceived) witty jokes, comical antics, or innappropriate stories that have little to do with the lesson at hand.
The students expect a focused, competent instructor acting and reinforcing a professional manner and demeanor. And although they may not comment if the teacher goes too far off track, they'll still notice, and that may diminish their respect for the teacher or even create less enthusisiasm… >>>