It was our high school orchestra director's first day back after being in a car accident, and one of his arms was in a sling. We had no idea what kind of a mood he'd be in, but one section of the orchestra soon found out. I don't remember if multiple players played the wrong note or didn't execute a dynamic in the score. I remember Mr. D. saying to them, however, "Does it say in the music to do (such-and-such?) " After they nodded and responded, "Yes," he snapped, "Then, do it, dammit."
He then mentioned the effect his pain medication was having on him, and I suspect everyone realized, "We'd better pay attention and play this piece to the best of our ability."
