David
If it makes you feel any better about your personal humiliation, I had a first instructor who would beat his dog (in front of me) if I performed badly. I was 14 or 15 at the time and therefore too young to entirely place the blame on the instructor, so therefore took a good proportion on my own shoulders.
I won't identify the instructor or the place, but if anyone else remembers the guy, I am talking a pipe-smoker in the East of the UK, in the late sixties or early seventies.
W