"Without knowing the OP or his airfield, it's hard to judge the severity of the incident, but the fact that he's here asking questions suggests that the lesson has not been learned."
I wouldn't say that its the case of lesson not learned, if said instructor was ranting on and took the kind of "huffy" approach well then maybe nothing has been explained, yes its been recognised that wrong has been done but not explained to the full extent and reasons why, everyones got to learn at some point and some of us learn the hard way as been shown here
Paul